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<div class="techs-only">
<p align="center">[<a href="#toc">Contents</a>] [<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/">Guidelines</a>]</p>
<div class="head">
<p><a href="http://www.w3.org/"><img height="48" width="72" alt="W3C" src="http://www.w3.org/Icons/w3c_home"/></a></p>
<h1><a name="title" id="title"></a>Implementing UAAG 2.0</h1>
<h2><a id="subtitle" name="subtitle"></a>A guide to understanding and implementing User Agent Accessibility Guidelines 2.0</h2>
<h2><a name="w3c-doctype" id="w3c-doctype"></a>W3C Working Draft 19 July 2011</h2>
<dl>
<dt>This version:</dt>
<dd><a href="http://www.w3.org/TR/2011/WD-IMPLEMENTING-UAAG20-20110719/">http://www.w3.org/TR/2011/WD-IMPLEMENTING-UAAG20-20110719/</a></dd>
<dt>Latest version:</dt>
<dd><a
href="http://www.w3.org/TR/IMPLEMENTING-UAAG20/">http://www.w3.org/TR/IMPLEMENTING-UAAG20/</a></dd>
<dt>Previous version:</dt>
<dd><a href="http://www.w3.org/TR/2010/WD-IMPLEMENTING-UAAG20-20100617/">http://www.w3.org/TR/2010/WD-IMPLEMENTING-UAAG20-20100617/</a></dd>
<dt>Editors:</dt>
<dd>James Allan, Texas School for the Blind and Visually Impaired</dd>
<dd>Kelly Ford, Microsoft</dd>
<dd>Jeanne Spellman, W3C/Web Accessibility Initiative </dd>
<dt>Previous Editors:</dt>
<dd>Jan Richards, Adaptive Technology Resource Centre, University of
Toronto</dd>
</dl>
<p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"> Copyright</a> ©2011 <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p>
<hr />
</div></div>
<div class="techs-only">
<h2 class="nonb"><a name="abstract" id="abstract">Abstract</a></h2>
<p>This document provides supporting information for the <a href="http://www.w3.org/TR/UAAG20/">User Agent Accessibility Guidelines (UAAG) 2.0</a> for designing <a class="dfn-instance"
href="#def-user-agent" rel="glossary" title="definition: User agent">user
agents</a> that lower barriers to Web accessibility for people with
disabilities. User agents include browsers and other types of software that
retrieve and render <a class="dfn-instance" href="#def-content"
rel="glossary" title="definition: Content">Web content</a>. A user agent that
<a href="#conformance">conforms</a> to these guidelines will promote
accessibility through its own user interface and through other internal
facilities, including its ability to communicate with other technologies
(especially <a class="dfn-instance" href="#def-assistive-technology"
rel="glossary" title="definition: Assistive technology">assistive
technologies</a>). Furthermore, all users, not just users with disabilities,
should find conforming user agents to be more usable. In addition to helping developers of browsers and media players, this
document will also benefit developers of assistive technologies because it
explains what types of information and control an assistive technology may
expect from a conforming user agent. </p>
<p>This document provides explanation of the intent of UAAG 2.0 success criteria, examples of implementation of the guidelines, best practice recommendations and additional resources for the guideline. </p>
<p>The "User Agent Accessibility Guidelines 2.0" (<acronym
title="Authoring Tool Accessibility Guidelines">UAAG</acronym> 2.0) is part
of a series of accessibility guidelines published by the <acronym
title="the World Wide Web Consortium">W3C</acronym> <a
href="http://www.w3.org/WAI/" title="Link to W3C-WAI">Web Accessibility
Initiative</a> (<acronym title="the Web Access Initiative">WAI</acronym>).</p>
<h2 class="nonb"><a name="status" id="status">Status of this document</a></h2>
<h3><a name="status-superseded" id="status-superseded"></a>May be
Superseded</h3>
<p><em>This section describes the status of this document at the time of its
publication. Other documents may supersede this document. A list of current
<acronym title="the World Wide Web Consortium">W3C</acronym> publications and
the latest revision of this technical report can be found in the <a
href="http://www.w3.org/TR/"><acronym
title="the World Wide Web Consortium">W3C</acronym> technical reports
index</a> at http://www.w3.org/TR/.</em></p>
<!-- COMMENT OUT FOR WORKING DRAFT -->
<!-- <h3><a name="status-status" id="status-status"></a>Editor's Draft of UAAG 2.0</h3> -->
<!-- <p><strong>This document is the internal working draft used by the <acronym title="User Agent Working Group">UAWG</acronym> and is updated continuously and without notice. This document has no formal standing within W3C. Please consult the <a href="http://www.w3.org/WAI/UA/">group's home page</a> and the <a href="http://www.w3.org/TR/">W3C technical reports index</a> for information about the latest publications by this group.</strong></p> -->
<!-- END COMMENT OUT FOR WORKING DRAFT -->
<!-- COMMENT OUT FOR EDITOR'S DRAFT -->
<h3><a name="status-status" id="status-status"></a>Working Draft of Implementing UAAG
2.0</h3>
<p>This is the W3C Working Draft of 19 July 2011. This draft includes new additions to Implementing UAAG 2.0 and some changes to the Guidelines identified through writing the Implementation document. There were no public comments in response to the previous draft. Substantial changes include: </p>
<ul>
<li>New intent, examples and resources for success criteria have been written by the group. The majority of success criteria are now complete with a short list of success criteria still to be written.
</li>
</ul>
<p><a name="status-feedback1" id="status-feedback1"></a><a name="status-feedback2" id="status-feedback2"></a>The Working Group seeks feedback on the following points for this draft: </p>
<ul>
<li>
Is the format of Implementing UAAG 2.0 useful to browser, media player, and other user agent designers, developers and project managers; AT vendors; and policy makers? Is additional information required for it to be useful? Is more detail or less detail needed?
</li>
<li>
Is the language for the <a href="#intro-def-useragent">tests determining a user agent</a> clear and understandable? Are the test conditions of a user agent complete?
</li>
</ul>
<p>Comments on this draft should be sent to <a href="mailto:public-uaag2-comments@w3.org">public-uaag2-comments@w3.org</a> (<a href="http://lists.w3.org/Archives/Public/public-uaag2-comments/">Public Archive</a>) <strong>by 19 August 2011</strong>.</p>
<p>UAAG 2.0 is not yet a Recommendation. The <a href="http://www.w3.org/WAI/UA/">User Agent Working Group</a> (UAWG) expects to advance UAAG 2.0 through the Recommendation track. Until that time <a href="http://www.w3.org/TR/UAAG10/">User Agent Accessibility Guidelines 1.0</a> (UAAG 1.0) <cite><a href="#ref-UAAG10">[UAAG10]</a></cite> is the stable, referenceable version. This Working Draft does not supersede UAAG 1.0. </p>
<!-- END COMMENT OUT FOR EDITOR'S DRAFT -->
<h3><a name="status-wai" id="status-wai"></a>Web Accessibility Initiative</h3>
<p>This document has been produced as part of the <acronym
title="World Wide Web Consortium">W3C</acronym> <a
href="http://www.w3.org/WAI/">Web Accessibility Initiative</a> (WAI). The
goals of the User Agent Working Group (UAWG) are discussed in the <a
href="http://www.w3.org/WAI/UA/2010/uawg_charter.html">Working Group charter</a>. The
<acronym title="User Agent Working Group">UAWG</acronym> is part of the <a
href="http://www.w3.org/WAI/Technical/Activity">WAI Technical
Activity</a>.</p>
<h3><a name="status-no-endorsement" id="status-no-endorsement"></a>No
Endorsement</h3>
<p>Publication as a Working Draft does not imply endorsement by the <acronym
title="the World Wide Web Consortium">W3C</acronym> Membership. This is a
draft document and may be updated, replaced or obsoleted by other documents
at any time. It is inappropriate to cite this document as other than work in
progress. </p>
<h3><a name="status-patents" id="status-patents"></a>Patents</h3>
<p> This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 W3C Patent Policy</a>. The group does not expect this document to become a W3C Recommendation. W3C maintains a <a
href="http://www.w3.org/2004/01/pp-impl/36791/status">public list of any patent disclosures</a> made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the W3C Patent Policy</a>. </p>
<hr />
</div>
<div class="toc">
<h2><a name="toc" id="toc">Table of Contents</a></h2>
<ul class="toc">
<li><a href="#abstract">Abstract</a></li>
<li><a href="#status">Status of this document</a></li>
<li><a href="#introduction">Introduction</a>
<ul class="toc">
<li><a href="#intro-def-ua">Definition of User Agent </a></li>
<li><a href="#intro-atag">Relationship with Authoring Tool Accessibility Guidelines 2.0 (ATAG)</a></li>
</ul>
</li>
<li><a href="#Guidelines">UAAG 2.0 Guidelines</a>
<ul class="toc">
<li><a href="#principle-perceivable">PRINCIPLE 1</a>: <span class="principle">Perceivable</span>
<ul class="toc">
<li><a href="#gl-access-alternative-content">Guideline 1.1</a>: Alternative content</li>
<li><a href="#gl-missing-alt">Guideline 1.2</a>: Missing content </li>
<li><a href="#gl-interaction-highlight">Guideline 1.3</a>: Highlighting</li>
<li><a href="#gl-text-config">Guideline 1.4</a>: Text configuration</li>
<li><a href="#gl-volume-config">Guideline 1.5</a>: Volume configuration</li>
<li><a href="#gl-speech-config">Guideline 1.6</a>: Synthesized speech configuration</li>
<li><a href="#gl-style-sheets-config">Guideline 1.7</a>: Style sheets configuration</li>
<li><a href="#gl-viewport-orient">Guideline 1.8</a>: Viewports</li>
<li><a href="#gl-focus-mechanism">Guideline 1.9</a>: Focus</li>
<li><a href="#gl-alternative-views">Guideline 1.10</a>: Source views</li>
<li><a href="#gl-info-link">Guideline 1.11</a>: Element Information</li>
</ul>
</li>
<li><a href="#principle-operable">PRINCIPLE 2</a>. Operable
<ul class="toc">
<li><a href="#gl-keyboard-access">Guideline 2.1</a>: Keyboard access</li>
<li><a href="#gl-sequential-navigation">Guideline 2.2</a>: Sequential navigation</li>
<li><a href="#gl-direct-navigation-and-activation">Guideline 2.3</a>: Direct navigation and activation</li>
<li><a href="#gl-search-text">Guideline 2.4</a>: Search</li>
<li><a href="#gl-nav-structure">Guideline 2.5</a>: Structured navigation</li>
<li><a href="#gl-device-independent-handlers">Guideline 2.6</a>: Event handlers</li>
<li><a href="#gl-store-prefs">Guideline 2.7</a>: Preference settings</li>
<li><a href="#gl-configure-controls">Guideline 2.8</a>: Toolbar configuration</li>
<li><a href="#gl-time-independent">Guideline 2.9</a>: Time-independence</li>
<li><a href="#gl-prevent-flash">Guideline 2.10</a>: Flashing</li>
<li><a href="#gl-control-inaccessible-content">Guideline 2.11</a>: Media </li>
</ul>
</li>
<li><a href="#principle-understandable">PRINCIPLE 3</a>: Understandable
<ul class="toc">
<li><a href="#gl-avoid-unnecessary-messages">Guideline 3.1</a>: Unnecessary messages</li>
<li><a href="#gl-avoid-mistakes">Guideline 3.2</a>: Mistakes </li>
<li><a href="#gl-doc-access-features">Guideline 3.3</a>: Documentation</li>
<li><a href="#gl-predictable-operation">Guideline 3.4</a>: Predictable</li>
</ul>
</li>
<li><a href="#principle-AT-access">PRINCIPLE 4</a>. Programmatic access
<ul class="toc">
<li><a href="#gl-AT-access">Guideline 4.1</a>: Assistive technology </li>
<li><a href="#gl-AT-access">Guideline 4.2</a>: Nested user agents </li>
</ul>
</li>
<li><a href="#principle-follow-specs">PRINCIPLE 5. Specifications and conventions</a>
<ul class="toc">
<li><a href="#gl-desktop-access">Guideline 5.1: Desktop apps</a></li>
<li><a href="#gl-obs-env-conventions">Guideline 5.2: Web & web apps</a></li>
<li><a href="#gl-implement-access-features">Guideline 5.3: Accessibility features</a></li>
<li><a href="#gl-render-to-spec">Guideline 5.4: Follow specifications</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#conformance">Conformance</a></li>
<li>Appendix A: <a href="#glossary">Glossary</a></li>
<li>Appendix B: <a href="#ref-this-doc">How to refer to UAAG 2.0 from other
documents</a></li>
<li>Appendix C: <a href="#references">References</a></li>
<li>Appendix D: <a href="#acknowledgments">Acknowledgements</a> </li>
<li>Appendix E: Checklist </li>
<li>Appendix F: Comparison of UAAG 1.0 guidelines to UAAG 2.0</li>
<li class="techs-only">Appendix G: <a href="#alternative-content-list">Alternative Content</a></li>
</ul>
</div>
<hr />
<h2><a name="introduction" id="introduction">Introduction</a></h2>
<div>
<h3><a id="intro-def-ua" name="intro-def-ua">Definition of <dfn>User Agent
</dfn></a></h3>
<p>A user agent is any software that retrieves, renders and facilitates end-user interaction with Web content. </p>
</div>
<div class="techs-only">
<h3><a name="intro-def-useragent" id="intro-def-useragent"></a>What qualifies as a User Agent?</h3>
<p>The following tests can be used to determine if software qualifies as a user agent for the purposes of these guidelines. It divides potential user agents into Primary Agents (the traditional "browser"), Extensions and Plug-ins, and Web-based User Agents. </p>
<p>If the following three conditions are met then it is a Primary User
Agent and Must Conform to UAAG:</p>
<ol>
<li>If it is a standalone application; and</li>
<li>If it interprets any w3c specified language; and</li>
<li>If it provides a user interface or interprets either a procedural
or declarative language that may be used to provide a user interface.</li>
</ol>
<p>If the following two conditions are met then it is a User Agent
Extension or Plug-In and Must Conform to UAAG:</p>
<ol>
<li>If it is launched by, or extends the functionality of, a Primary
User Agent; and </li>
<li>If post-launch user interaction either becomes part of, or is
within the bounds of, the Primary User Agent.</li>
</ol>
If the following three conditions are met then it is a Web-Based User
Agent and Must Conform to UAAG:
<ol>
<li>If the user interface is generated by the interpretation of either
a procedural or declarative language; and</li>
<li>If this interpretation is by a Primary User Agent, User Agent
Extension or Plug-In; and</li>
<li>If user interaction is not passed to and from the Primary User
Agent, User Agent Extension or Plug-In, or if user interaction does
not modify the Document Object Model of its containing document.</li>
</ol>
<hr />
<!-- techs-only --></div>
<h3><a name="intro-atag" id="intro-atag"></a>Relationship to the Authoring Tool Accessibility Guidelines (ATAG) 2.0</h3>
<p>While it is convenient to think of user agents retrieving and rendering web content for one group of people (end-users) that was previously authored by another group (authors), user agents are frequently involved with the process of authoring content.</p>
<p>
For these cases, it is important for user agent developers to consider the application of another W3C-WAI Recommendation, the Authoring Tool Accessibility Guidelines (ATAG). ATAG (currently 2.0 is in draft) provides guidance to the developers of tools regarding the accessibility of authoring interfaces to authors (ATAG 2.0 Part A) and ways in which all authors can be supported in producing accessible web content (ATAG 2.0 Part B).
</p>
<div class="techs-only">
<h3><a name="intro-atag-role" id="intro-atag-role"></a>The Role of User Agents in Web Authoring</h3>
<p>The following is a list of several ways in which user agents are commonly involved in web content authoring and the relationship between UAAG 2.0 and ATAG 2.0. </p>
<ol type="1">
<li>Preview tool: As authors edit web content, they often preview their work in user agents to test how the content will be appear and operate.
<ul><li>ATAG 2.0 includes a special exception when "Previews" are implemented with pre-existing user agents, so there are no additional requirements on user agent developers in this case.</li></ul></li>
<li>Checking tool: Authors often make use of user agent error panels (e.g. HTML validity, JavaScript errors, etc.) during authoring.
<ul><li>ATAG 2.0 Part A would apply, but likely would not include any additional accessibility requirements beyond what is in UAAG 2.0. </li>
<li>If a user agent includes an "accessibility checker", then the developer should consult checker implementation guidance in ATAG 2.0 Part B.</li></ul></li>
<li>Edit modes: Some user agents include a mode in which the user can edit and save changes to the web content, modifying the experience of other users.
<ul><li>In this mode, the user agent is acting as an authoring tool and all of ATAG 2.0 would apply. </li></ul></li>
<li>Automatic content changes: Some user agents (and/or user agent plug-ins) may automatically make changes to the retrieved web content before it is rendered.
<ul><li>This functionality is not considered an authoring tool because the changes are made to the user's own experience, not the experience of other users.</li></ul></li>
<li>Providing a platform for web-based authoring tools: Many web applications serve as authoring tools and they make use of user agent features in order to deliver their functionality (e.g., undo text entry, adjust font size of the authoring tool user interface etc.)
- User agent developers should consult ATAG 2.0 to understand the ways in which web-based authoring tools can depend on user agent features. </li>
</ol>
<!-- techs only --></div>
<h2><a name="Guidelines" id="Guidelines"></a>UAAG 2.0 Guidelines</h2>
<p>The success criteria and applicability notes in this section are <a class="dfn-instance" href="#def-normative"
title="definition: Normative">normative</a>. Guideline summaries are informative. </p>
<div class="principle">
<h2 class="pr-title"><a name="principle-perceivable"
id="principle-perceivable"></a>PRINCIPLE 1 - Perceivable</h2>
<p class="pr-text">Ensure that the user interface
and rendered content are perceivable</p>
</div>
<div class="guideline">
<h3 class="gl-title">
<a name="gl-access-alternative-content" id="gl-access-alternative-content"></a>
<span class="techs-only">Implementing </span>
Guideline 1.1 - Alternative Content</h3>
<p class="gl-text">Provide access to alternative content. </p>
<p class="summary" id="summary11"><strong>Summary</strong>: The user can easily determine which pieces of content have alternatives such as alt text or longdesc (1.1.1) and interact with the text to see the available
alternatives (1.1.3). The user can also choose at least one alternative such as alt text to be always displayed (1.1.2), but it's recommended that users also be
able to specify a cascade (1.1.4), such as alt text if it's there, otherwise longdesc, otherwise filename, etc.
</p>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-111">1.1.1 Configurable Default
Rendering: </h4>
<p class="sc-text"> The user can specify which types of <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a> to render by default. <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.1.1:</strong> <br />
When the author provides alternative content, it is wasted if the user agent doesn't render it for users who need it. Default alternative content is a global option because it is an unreasonable burden for users to change the rendering options every time they visit a new page. </li>
<li><strong>Examples of Success Criterion 1.1.1:</strong>
<ul>
<li>Sally is blind. In the browser's preferences dialog box, Sally specifies that she wants alt text displayed in place of images, and that the document should reflow to allow the entire alt text to be displayed rather than truncated. </li>
<li>In the browser's preferences dialog box, Ben chooses to always display the alternative ("fallback") content for embedded objects, such as videos. </li>
<li>Brin is deaf. She toggles a menu item which turns on the display of all captions for video and audio content. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.1.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-112">1.1.2 Browse and Render:</h4><p class="sc-text">
When a rendered element has <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>, the user can render alternatives according to the following: <span class="level"><span class="level">(Level A)</span> </span> </p>
<ul>
<li>synchronized alternatives for time-based media (e.g. captions, audio descriptions, sign language) can be rendered at the same time as their associated audio tracks and visual tracks, and</li>
<li>non-synchronized alternatives (e.g. short text alternatives, long descriptions) can be rendered as replacements for the original rendered content.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.1.2:</strong> <br />
a. There are times when users cannot gain meaningful information from images, charts, graphs, etc. (non-time-based media elements).The author may have provided synchronized alternatives for the media. Users should be able to easily discover the synchronized alternatives provided, and have them render synchronously with the default media. <br />
<br />
b. There are times when a user cannot gain meaningful information from a non-time-based media element (images, charts, graphs, etc.). The author may have provided alternatives for this. The user should be able to easily discover the alternatives provided, and have them render in place of the default media.</li>
<li><strong>Examples of Success Criterion 1.1.2:</strong>
<ol type="a">
<li>Sam is deaf. He is watching a video on a web page. He cannot hear the audio. The author has provided captions for the video. The user agent detecting that captions exist, makes the caption button visible. The caption button toggles the captions on/off. </li>
<li>Sue is blind. She is watching a video on a web page. She cannot see the action on the screen. The author has provided audio-descriptions for the video. The user agent detecting that audio-descriptions exist, makes the AD button visible. The button toggles the audio-descriptions on/off. </li>
<li>Mary has a learning disability. She is reading a page with many images. The images are distracting. Mary is able to turn the images off, and reveal the alternative text (@alt) that the author provided. The alternative text is rendered in place of the images. Mary has the option of having the size of the image remain same or fit the size of the text. </li>
<li>Mary also cannot make sense of the graphs. The author has provided long descriptions for the graphs. Mary toggles the long-description feature. The browser detects the presence of valid @long-descriptions and renders an actionable icon inline after an image. Mary can click on the icon, opening the long-description for that particular graph.</li>
</ol>
</li>
<li><strong>Related Resources for Success Criterion 1.1.2:</strong>
<ul>
<li>See Success Criterion 4.1.2 : Name, Role, State, Value,
Description</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-113">1.1.3 Identify Presence of Unrendered Alternative Content: </h4><p class="sc-text">The user can specify that content be rendered with an adjacent indicator when unrendered <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a> is present (e.g. an icon to indicate an image has a short text alternative). <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.1.3:</strong> <br />
When the author provides alternative content, it is wasted if users cannot find it. The user agent should make the presence of alternative content evident to the user. Users should not have to hunt and examine every time to see if it includes such content, because such searching can be time-consuming, especially for users whose disability makes input difficult, tiring, or painful. The user should be able to easily identify which items have alternative content, rather than being merely informed that alternative content is somewhere in the view. </li>
<li><strong>Examples of Success Criterion 1.1.3:</strong>
<ul>
<li>Tinan has repetitive strain injuries and seeks to limit scrolling. The user agent renders distinct visual icons in proximity of content that has short text alternatives, long descriptions, and captions. If the icon forces the text to extend beyond a fixed size container the user agent uses global preference settings to determine whether to expand the container, provide scroll bars, or truncate the content. </li>
<li>Aosa is blind. When rendering a Web page using synthesized speech, the user agent generates an audible tone to signify the word being read is an acronym, and Aosa can press the * key to hear the expansion. When the phrase being read is the Alt text for an image, another tone indicates that Aosa can press + to hear the longdesc. </li>
<li>A button is displayed beneath the playing video to indicate that captions are available and to let the user toggle their display. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.1.3:</strong>
<ul>
<li>(Refer to the SC about handling layout/reflow options.) </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-114">1.1.4 Rendering Alternative
(Enhanced)</h4>
<p class="sc-text">: The user can specify the cascade order in which to render <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>. <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.1.4:</strong> <br />
For a given piece of non-text content the author may have provided one or several alternatives. For example, an image may have different versions based on resolution, ‘alt text’ (@alt) or a link to a long description (@longdesc). A video may have bandwidth alternatives, caption files in different languages, and audio descriptions in different languages. Users can choose which item(s) to render by default, and specify the order of the cascade of alternatives to be rendered if the author did not provide a type of alternative.</li>
<li><strong>Examples of Success Criterion 1.1.4:</strong>
<ul>
<li>Mary has a learning disability. She finds looking at images on a web page very distracting. Mary would like to see all images rendered in the following order. First, for images with long descriptions have the long description rendered in place of the image. If the long description does not exit, she wants the ‘alt text’ to be rendered. If neither is available, Mary wants the file name rendered. <br /><br />
Added functionality would allow Mary to right click (context menu) on an image to list and select the rendering of the available alternatives (thumbnail, original size, full screen, low resolution, high resolution, alt text, long description, file name) </li>
<li class="editor-notes">@@ Editors' Note: where do we put the ability for the user to individually pick an image and have the image displayed. It should not have to be an all or nothing. @@</li>
<li> Juan is hard of hearing. He wants to always see video on the page. Also, Juan would like the Spanish language track used if available, along with Spanish captions as a default. If these are not available, he wants to see the video with English audio and captions. If no captions are available Juan wants the the video and English audio. <br /><br />
Added functionality would allow Juan to right click (context menu) on an video to list and select the rendering of the available alternatives (still image, caption languages, audio languages, audio-description languages)</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.1.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-missing-alt" id="gl-missing-alt"></a>
<span class="techs-only">Implementing </span>
Guideline 1.2 - Repair missing content. </h3>
<p class="summary" id="summary12"><strong>Summary</strong>: The user can request useful alternative content when the author fails to provide it. For example, showing a filename in place of missing (1.2.1) or empty (1.2.2) alt text.</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-121">1.2.1 Repair Missing
Alternatives:</h4>
<p class="sc-text"> The user can specify whether or not the user agent should generate and render <a class="dfn-instance" href="#def-repair-text"
title="definition: repair text">repair text</a> (e.g. file name) when it <a class="dfn-instance" href="#def-recognize"
title="definition: Recognize">recognizes</a> that the author has not provided <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>. <span class="level"><span class="level">(Level A)</span> </span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.2.1:</strong> <br />
When alternative content is missing, it is sometimes useful for users
have access to alternative information, such as the
filename. Users need to control the flow of this
information, because an uncontrolled flow can be distracting and time-consuming. This is particularly important for users with some disabilities, who may not be able to use some forms of content (e.g. images) or may even need to avoid some forms of content (e.g. animations) and therefore choose to replace them with alternative content. <br />
<br />
Users need to control the flow of the content when this information is added, because in some cases cases truncating the content to fit its container will make the document unusable (e.g. if important information becomes hidden), while in other cases expanding the container will make the document unusable (e.g. when important cues no longer line up correctly).</li>
<li><strong>Examples of Success Criterion 1.2.1:</strong>
<ul>
<li>Ray is blind and counts on alternative text descriptions for images. There is an image in web content that does not have alternative
text provided. The browser displays the string '(image canoe.png)', which includes the file name because that is the
only available information about the image.</li>
<li>Bintu is deaf and relies on captions to replace audio. A video does not have captions. Bintu selects a caption
button, and is informed that no captions exist. The player
then analyzes the video soundtrack and provides speech to text
translation served as captions. <strong>Note</strong>: this is an advanced example, not a requirement.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.2.1:</strong>
<ul>
<li><a href="http://www.w3.org/WAI/eval/Overview.html">Evaluating Web Sites for Accessibility: Overview</a></li>
</ul>
</li>
</ul>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-122">1.2.2 Repair Empty
Alternatives:</h4><p class="sc-text"> The user can specify whether or not the user agent should generate and render repair text (e.g. file name) when it recognizes that the author has provided <a class="dfn-instance" href="#def-empty-content"
title="definition: Empty content">empty</a> alternative content. <span class="level">(Level AA)</span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.2.2:</strong> <br />
When an author has chosen to code web content for alternative text but
not provide any text information (e.g. an empty alt) the user may still
need to know any information available about that web content. Some authoring tools may insert empty alternative text by default, even though this is is contrary to accessibility guidelines, and this can prevent users from getting useful information about the element.</li>
<li><strong>Examples of Success Criterion 1.2.2:</strong>
<ul>
<li>A user wanting additional information on an image can right click on an image to get a context menu, then choose properties to get available information about the image without have to find the image in the source code.</li>
<li>A photo-sharing web site automatically generates web content
with text alternatives. When the photos are initially uploaded, or if
the person posting the photos chooses not to caption a photo, an
empty text alternative is automatically generated. A person with visual
impairments uploads a batch of photos and needs to know which photo is
which in order to provide the photo description. The user agent provides
a menu option that displays all known information about that file
including filename and selected camera info (date, time, size, type, etc.). </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.2.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-123">1.2.3 Repair Missing Associations:</h4><p class="sc-text"> The user can specify whether or not the user agent should attempt to predict associations from author-specified presentation attributes (i.e. position and appearance). <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.2.3:</strong> <br />
To be written</li>
<li><strong>Examples of Success Criterion 1.2.3</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.2.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-124">1.2.4 Broken Alternative Content: </h4>
<p class="sc-text">The user can be notified when the user agent cannot render alternative content (e.g. when captions are broken).</p> <span class="level">(Level AAA)</span>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.2.4:</strong> <br />
Users who have chosen to have alternative content presented to them greatly appreciate understanding whether a non-working requests is due to a source error, user error, or merely a delay. Users who lack this information may incorrectly conclude that a particular site is not accessible to them, or may waste time either waiting for content or attempting to find a non-existent problem in their browser or configuration. Note that it is generally recommended that this type of notification NOT require user response, so as not to interrupt the user's experience. </li>
<li><strong>Examples of Success Criterion 1.2.4</strong>
<ul>
<li>_____ has images turned off and replaced by their alt text. When alt text is missing, an error icon is presented in its place.</li>
<li>_____ is watching videos embedded in a Web page. The browser enables a Captions button when it detects that a caption stream is available. The user clicks this to turn on display of captions, but the browser finds the caption stream is invalid. Instead of merely showing blank space, it displays a small message or icon in the caption area to inform the user that the requested captions cannot be displayed. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.2.4:</strong>
<ul>
<li>Success criterion 1.1.3 requires that the user be informed when the document indicates that alternative content is present, but the browser may not know that the alternative content is broken until the user actually attempts to render or play it.</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-interaction-highlight" id="gl-interaction-highlight"></a>
<span class="techs-only">Implementing </span>
Guideline 1.3 - Provide highlighting for
selection, keyboard focus, enabled elements, visited links.
</h3>
<p class="summary" id="summary13"><strong>Summary</strong>: The user can visually distinguish selected, focused, and enabled items, and recently visited links (1.3.1), with a choice of highlighting options that at least include foreground and background colors, and border color and thickness (1.3.2).</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-131">1.3.1 Highlighted Items:</h4>
<p class="sc-text">The user can globally specify that the following be highlighted so that each class is uniquely distinguished. It is not the intention that all recognized enabled elements be uniquely distinguished, just that they be distinguished from disabled elements. <span class="level">(Level A)</span></p>
<ol type="a">
<li>selection </li>
<li>active keyboard focus (indicated by focus cursors and/or text cursors) </li>
<li>active window </li>
<li>active viewport </li>
<li>recognized enabled elements </li>
<li>presence of alternative content </li>
<li>recently visited links </li>
</ol>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.3.1:</strong> <br />
Users need to be able to easily discover what web content they can interact with. Users with low vision need to be able to highlight selection, content focus, enabled elements and links (including recently visited links) in order to successfully discover and interact with the web content. <br /><br />
Note: In addition to these required categories, it is recommended that user agents also allow the user to highlight the active viewport, even when it is a frame or similar within the active window, which makes it much easier for the user to visually locate the active focus.<br /><br />
Note: Platform conventions will dictate whether or not an inactive keyboard focus (keyboard focus in an inactive viewport) is visually indicated by an inactive cursor.<br /><br />
Note: the definition of visited and unvisited links is up to the user agent. In some cases it might be links visited during the current session, or in other cases links visited in the browser's history until that is cleared.</li>
<li><strong>Examples of Success Criterion 1.3.1:</strong>
<ul>
<li>A web site uses styles to override visited link color. A low vision user wants to know what links have yet to be explored. The user agent provides a dialog box for setting overrides to author-selected link colors. </li>
<li>An author has created a web site with CSS styles that removes the content focus outline. The user agent provides a dialog box for setting overrides to authors CSS focus outline declaration. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.3.1:</strong>
<ul>
<li>UAAG 1.3.2 Highlighting Options, describes user options to configuring how these categories are highlighted </li>
<li>UAAG 2.1.? Keyboard Focus requires every window have an active or inactive keyboard focus at all times </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-132">1.3.2 Highlighting Options:</h4>
<p class="sc-text">
When highlighting classes specified by <a href="#sc-131">1.3.1 Highlighted Items</a> and <a href="#sc-131">1.3.3 Highlighted Input Controls</a>, The user can specify highlighting options that include at least: <span class="level"><span class="level">(Level A)</span> </span></p>
<ul>
<li><strong class="handle">(a) foreground colors</strong>, </li>
<li><strong class="handle">(b) background colors</strong>, and </li>
<li><strong class="handle">(c) border</strong> (configurable color, style, and thickness)</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.3.2:</strong> <br />
A low vision user needs control over what visual properties work best for
highlighting. These include foreground colors, background colors, and
visual borders (with the same configurable range as the operating environment's conventional selection utilities)</li>
<li><strong>Examples of Success Criterion 1.3.2:</strong>
<ul>
<li>A low vision wants to know where the text boxes are on a web form. The
user wants to set a thick black border around all text boxes. The user
agent provides a dialog box allowing the user to override any author
settings.</li>
<li class="editor-notes">@@ Editors' Note: provide more than 2 options of highlighting options @@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.3.2:</strong>
<ul>
<li><a href="http://www.w3.org/TR/CSS21/box.html#propdef-border-style">CSS 2 specification</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-133">1.3.3 Highlighted Input Controls:</h4>
<p class="sc-text">The user can have the following highlighted when they are recognized:
<span class="level">(Level AA)</span> </p>
<ul>
<li>(a) enabled controls that take input (e.g. push buttons, radio buttons, check boxes, and text input fields, but not groupings or static text and images) regardless of whether they are read-write or read-only, and </li>
<li>(b) elements with scripted input handlers (e.g. images or text ranges that have onClick or onKeyPress events) regardless of whether the current state allows them to operate.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.3.3:</strong> <br />
When a user looks at a page they often want to quickly find the control they need to accomplish their task, yet in some pages the controls may be "buried" amid a large amount of other content, or may be styled to make it very hard to distinguish from other content. This can be particularly difficult for people with visual impairments, who may not be able to easily distinguish visual differences that may be subtle or obvious to users with average vision. It can also be a problem for people with some cognitive impairments, who may have difficulty distinguishing between items with similar or non-standard appearance. The ability to have these items visually distinguished can greatly help reduce the amount of time or number of commands they need to use examining a page. This success criterion works in conjunction with 1.3.1 Highlighted Items, which ensures highlighting of several other classes of information, and with 1.3.2 Highlighting Options, which ensures that the user can
customize the highlighting to meet their visual or cognitive needs.</li>
<li><strong>Examples of Success Criterion 1.3.3:</strong>
<ul>
<li>Binh gets easily frustrated when he cannot locate the buttons and links on a page, usually because they don't have the standard appearance he's used to. By turning on the option to have all links appear in bright purple, and all push buttons and the like drawn with a bright purple border, he can easily scan the page and find the items he's looking for.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.3.3:</strong>
<ul>
<li>1.1.3 Identify Presence of Alternative Content (Level A) requires items with alternative content to be highlighted.</li> <li>1.3.1 Highlighted Items (Level A) requires highlighting of additional classes, including the selection, the active keyboard focus, and visited and unvisited links. </li>
<li>1.3.2 Highlighting Options (Level A) requires the user be able to customize the appearances of these highlights. </li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-text-config" id="gl-text-config"></a>
<span class="techs-only">Implementing </span>
Guideline 1.4 - Provide text configuration.
</h3>
<p class="summary" id="summary14"><strong>Summary</strong>: The user can control text font, color, and size (1.4.1), including whether all text should be the shown the same size (1.4.2).</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-141">1.4.1 Configure Text: </h4><p class="sc-text"> The
user can globally set the following
characteristics of visually <a class="dfn-instance" href="#def-rendered-text"
title="definition: rendered text">rendered text</a> content, <a
class="dfn-instance" href="#def-override"
title="definition: Override">overriding</a> any specified by the <a
href="#def-author">author</a> or user agent defaults: <span class="level"><span class="level">(Level A)</span> </span> </p>
<ul>
<li><strong class="handle">(a) text scale</strong> (i.e. the general size
of text) ,</li>
<li><strong class="handle">(b) font family</strong>, and</li>
<li><strong class="handle">(c) text color</strong> (i.e. foreground and
background).</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.4.1:</strong> <br />
Users need to able to access a wide range of
font sizes, styles, colors, and other attributes in order to find the
combination that works best for their particular needs. For example,
some users want to increase font size to make text more legible, while
other users want to reduce the font size to decrease the need to scroll the content. In providing these preferences, it is important to avoid making assumptions. For example, some users want to reduce the font size to decrease the need to scroll the content.</li>
<li><strong>Examples of Success Criterion 1.4.1:</strong>
<ul>
<li>Lee has low vision from albinism and has difficulty with screen resolution and brightness. She chooses to have all text displayed in Palatino font, with white text on a black background, and at least 16 points tall. The serif Palatino font has character spacing that resolves better for her vision, while the white on black reduces glare and the larger size allows her to distinguish fine detail more clearly.</li>
<li>Tomas has extremely low vision and chooses to have his browser display all text the same size, and sets that size as large as he can without making the letters too tall for his screen. He chooses not to have headings be proportionately larger than normal text because that would make them taller than his screen and so unreadable.</li>
<li>Browser A supports only 3 font sizes: Small, Medium, and Large. Lee, who has low vision, needs to use a font size of 16 pt, which is between the medium and large sizes. Browser A provides an option to override the 3 font sizes with the operating system font range, so that Lee can select the 16 pt font size she needs. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.4.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-142">1.4.2 Preserving
Size Distinctions:</h4><p class="sc-text"> The user can specify whether or not distinctions in the size of <a class="dfn-instance" href="#def-rendered-text"
title="definition: rendered text">rendered text</a> are preserved when that text is rescaled (e.g. headers continue to be larger than body text). <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.4.2:</strong> <br />
The relative size of text provides visual cues that help in understanding and navigating web content and because some content may be authored in a way that would make it difficult or impossible to understand when if font distinctions were hidden. For example, headlines in a larger font than the body text. Users who set preferences to enlarge or reduce the text size need to have these visual cues preserved.</li>
<li><strong>Examples of Success Criterion 1.4.2:</strong>
Lee finds text easiest to read at 16 pt Palatino, but can chooses to have her browser display all in the Palatino font and at least 16 pt in size. She needs the headlines to scale proportionally (e.g. 24 pt) in order to preserve headline prominence.</li>
<li><strong>Related Resources for Success Criterion 1.4.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-volume-config" id="gl-volume-config"></a>
<span class="techs-only">Implementing </span>
Guideline 1.5 - Provide volume configuration.
</h3>
<p class="summary" id="summary15"><strong>Summary</strong>: The user can adjust the volume of each audio track relative to the global volume level (1.5.1).</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-151">1.5.1 Global Volume:</h4><p class="sc-text">
The user can independently
adjust the volume of all <a class="dfn-instance" href="#def-audio-track"
title="definition: Audio track">audio tracks</a>, relative to the global volume level set
through <a class="dfn-instance" href="#def-operating-environment"
title="definition: Operating environment">operating environment</a> mechanisms. However, the user agent may only override a global mute on explicit user request and if the user has been cautioned about the implication. <span class="level">(Level A)</span></p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.5.1:</strong> <br />
User agents can render audio tracks from a variety sources, and in
some cases, multiple audio tracks may be present on a single page.
Users should be able to globally set the volume of audio tracks, rather
than having to adjust the volume of each audio track being played.</li>
<li><strong>Examples of Success Criterion 1.5.1:</strong>
<ul>
<li>An operating system provides a master audio volume control that
applies to all audio tracks rendered within the environment, including
the user agent. The user may define a default volume level through a
preferences dialog that is retained across sessions.</li>
<li>A user encounters a page with two advertisements and one video which
begins playback on page load complete. A global mute command, supported
via a mute key on the user's keyboard, allows the user to immediately
silence the playing audio tracks. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.5.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<br clear="all" class="sc-close" />
</div>
<h3 class="guideline">
<a name="gl-speech-config" id="gl-speech-config"></a>
<span class="techs-only">Implementing </span>
Guideline 1.6 - Provide synthesized speech configuration.
</h3>
<p class="summary" id="summary16"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-161">1.6.1 Speech Rate and Volume: </h4>
<p class="sc-text">If synthesized speech is produced, the user can specify the following: <span class="level"><span class="level">(Level A)</span> </span> </p>
<ul>
<li><strong class="handle">speech rate</strong> and </li>
<li><strong class="handle">speech volume</strong> (independently of
other sources of <a class="dfn-instance" href="#def-audio"
title="definition: Audio">audio</a>).</li>
</ul>
<h4 class="sc-title" id="sc-162">1.6.2 Speech Pitch and Range:</h4><p class="sc-text"> The user can specify the following for synthesized speech: <span class="level">(Level AA)</span> :</p>
<ul>
<li><strong class="handle">(a) pitch</strong> ("pitch" refers to the
average frequency of the speaking voice), and </li>
<li><strong class="handle">(b) pitch range</strong> ("pitch range"
specifies a variation in average frequency),</li>
</ul>
<h4 class="sc-title" id="sc-163">1.6.3 Advanced Speech Characteristics:</h4><p class="sc-text"> The
user can specify all of the speech characteristics offered by the speech
synthesizer. <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.6.1, 1.6.2, 1.6.3:</strong> <br />
The objective of these success criteria is to allow the user to customize the specified speech characteristics to settings that allow the user to perceive and understand the audio information.<br />
<br />
Users may need to increase the volume to a level within their range of perception for example. Users may also wish to increase the rate of synthesized speech presentation because they can understand it at a rate faster than the default setting of the user agent.<br />
<br />
Success criterion 1.6.1 covers the characteristics that users most commonly need to adjust and that are adjustable in most technologies, while success criterion 1.6.2 covers characteristics that are less widely altered and less widely supported. </li>
<li><strong>Examples of Success Criterion 1.6.1, 1.6.2, 1.6.3:</strong>
<ul>
<li>A telephone-based web browser starts reading back a web page. The user can press a key to increase the rate at which the information is read back. Similarly, the user may be using this telephone browser in a noisy environment such as a crowded subway. With a key press the user can quickly increase the volume of the speech being heard.</li>
<li class="editor-notes">@@ Editors' Note: Add an example for 1.6.2 @@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.6.1, 1.6.2, 1.6.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-164">1.6.4 Synthesized Speech Features:</h4><p class="sc-text"> For synthesized speech, the following features are provided: <span class="level">(Level AA)</span> </p>
<ul>
<li><strong class="handle">(a) user-defined extensions</strong> to the
synthesized speech dictionary,</li>
<li><strong class="handle">(b) "spell-out"</strong>, where text is spelled
one character at a time, or according to language-dependent pronunciation
rules,</li>
<li><strong class="handle">(c) at least two ways of speaking numerals:
</strong>one where numerals are spoken as individual digits and punctuation (e.g. "one two zero three point five" for 1203.5 or "one comma two zero three point five" for 1,203.5), and
one where full numbers are spoken (e.g. "one thousand, two hundred
and three point five").</li>
<li><strong class="handle">(d) at least two ways of speaking
punctuation:</strong> one where punctuation is spoken literally, and one
where punctuation is rendered as natural pauses.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.6.4:</strong> <br />
The synthetic speech presentation of text can be difficult to understand at times. Success criteria here are aimed at giving the user the ability to adjust the way in which the speech synthesizer presents text to improve understandability.<br />
<span class="editor-notes">@@ Editors' Note: Add text on treatment of currency and international customs for reading currency numbers. @@</span></li>
<li><strong>Examples of Success Criterion 1.6.4:</strong>
<ul>
<li>The speech synthesizer incorrectly pronounces technical terms employed in the user's organization. These terms are consistently mispronounced in a way that makes it difficult for the audio user to distinguish them, even though they are instantly distinguishable when displayed as text.. A dictionary allows the user to enter a spelling of the name that produces the correct pronunciation from the synthetic speech. </li>
<li>A speech synthesizer is repeating a phone number. The user wishes to easily copy this number so switches to a mode where each digit is spoken as a unique word e.g. five, five, five and so on. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.6.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-style-sheets-config" id="gl-style-sheets-config"></a>
<span class="techs-only">Implementing </span>
Guideline 1.7 - Provide style sheets configuration.
</h3>
<p class="summary" id="summary17"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-171">1.7.1 Author Style Sheets:</h4><p class="sc-text">
If one or more <a class="dfn-instance" href="#def-author-styles"
title="definition: Author styles">author style
sheets</a> are defined, the user has the following options: <span class="level"><span class="level">(Level A)</span> </span> </p>
<ul>
<li><strong class="handle">(a)</strong> select and apply one or more author style sheets, or </li>
<li><strong class="handle">(b)</strong> turn off author style sheets.</li>
</ul>
<h4 class="sc-title" id="sc-172">1.7.2 User Style Sheets:</h4><p class="sc-text"> If
one or more <a href="#def-user-styles">user style
sheets</a> are defined, the user has the following options: <span class="level"><span class="level">(Level A)</span> </span> </p>
<ul>
<li><strong class="handle">(a)</strong> select and apply one or more user style sheets, or </li>
<li><strong class="handle">(b)</strong> turn off user style sheets.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.7.1 & 1.7.2:</strong> <br />
CSS stylesheets allow for extensive customization of the rendering of web content. Such customization is frequently used to make web content accessible to a wide range of user needs. These success criteria ensure that users of web browsers can fully take advantage of the stylesheets offered by web authors or that the users have created.</li>
<li><strong>Examples of Success Criterion 1.7.1 & 1.7.2:</strong>
<ul>
<li>A user finds yellow text on a black background easiest to read. When a web site is loaded, the user agent provides a menu where the user can select between several stylesheets that the web author has created for the web site. The user selects a stylesheet named yellow on black from a menu in the user agent listing all available stylesheets. The web content is then rendered using this stylesheet.</li>
<li>On a shared computer a web site is rendered with black text on a white background that is normally in full color. The user agent provides a menu where the user can de-select a user-defined stylesheet has been applied to the web page and the user easily disables this stylesheet. The web site is now rendered in full color. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.7.1 & 1.7.2:</strong>
<ul>
<li><a href="http://www.w3.org/TR/CSS2/cascade.html#cascade">CSS 2 Recommendation: cascade weight rules</a></li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline">
<a name="gl-viewport-orient" id="gl-viewport-orient"></a>
<span class="techs-only">Implementing </span>
Guideline 1.8 - Help users to use viewports and orient within viewports.
</h3>
<p class="summary" id="summary18"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-181">1.8.1 Highlight Viewport:</h4>
<p class="sc-text">The <a class="dfn-instance" href="#def-viewport"
title="definition: viewport">viewport</a> with the <a class="dfn-instance"
href="#def-input-focus" title="definition: input focus">input focus</a> (including nested viewports and their containers) is highlighted, and the user can customize attributes of the <a class="dfn-instance" href="#def-highlight"
title="definition: Highlight">highlighted</a> mechanism, including, but not limited to, shape, size, stroke width, color, and blink rate (if any). <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.1:</strong> <br />
When a user agent presents content using multiple viewports, users
benefit from a clear indication of which viewport has focus. Simply
relying upon text foreground and background colors to indicate focus
may not provide sufficient, visually perceivable indication for users
with low vision. Highlighting of viewport frames using both color,
with sufficient contrast, and increase in viewport border thickness
can provide multiple visual cues that indicate focus.</li>
<li><strong>Examples of Success Criterion 1.8.1:</strong>
<ul>
<li>A music Web site allows the user to select which of the top 10 songs
are available for listening. Each song is presented in a graphical
viewport providing a music player. Using a keyboard based screen
magnification tool, a low vision user tabs between songs, with the
currently selected player viewport highlighted with a thick, yellow
border against a dark gray background.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-182">1.8.2 Move Viewport to Selection and Focus: </h4>
<p class="sc-text"> When a viewport's <a class="dfn-instance" href="#def-selection"
title="definition: Selection">selection</a> or <a class="dfn-instance"
href="#def-input-focus" title="definition: input focus">input focus</a> changes, the <a
class="dfn-instance" href="#def-viewport"
title="definition: viewport">viewport</a>'s content moves as necessary to ensure that the new selection or input focus location is at least partially in the visible portion of the viewport. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.2:</strong> <br />
When content is presented within a viewport and the content extends
horizontally or vertically beyond the visible bounds of the viewport,
the user must be able to move to a selectable element or elements
which may be out of view, and to have the selected content
automatically move into view. For keyboard based users and users of
screen magnification tools, this allows users an efficient means to
view selected content without having to utilize scrolling controls to
locate and view the selection. </li>
<li><strong>Examples of Success Criterion 1.8.2:</strong>
<ul>
<li>A screen magnification user is performing a spell check of a blog
posting that is contained within a scrollable viewport. The text of
the blog posting exceeds the vertical size of the viewport. The
blogging software provides a key to move to the first, and then any
subsequent, unrecognized words. With two unrecognized words in the
posting, the user ignores the first selected word, and presses the
keystroke to move to the next which is currently out of view in the
last sentence of the posting. As the key is pressed, the viewport
scrolls to show the selected word. </li>
<li>A user of a screen reader is showing a sighted colleague how to
complete a registration form contained within a viewport. The form
exceeds the vertical bounds of the viewport, requiring vertical
scrolling to view the complete form content. As the screen reader
completes each form entry and presses the tab key, the next form
control in the tab order scrolls into view if it is not already
visible in the viewport. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-183">1.8.3 Resizable: </h4>
<p class="sc-text">The user can make graphical viewports
resizable, within the limits of the display, <a class="dfn-instance"
href="#def-override" title="definition: Override">overriding</a> any values
specified by the <a href="#def-author">author</a>. <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.3:</strong> <br />
If a graphical viewport contains content that exceeds the dimensions
of the viewport, users should have the option to increase the size of
the viewport to allow the full image to be displayed without
scrolling, within the limits of the physical display screen. This
benefits keyboard users who may find it difficult to scroll content
and users with cognitive or learning disabilities whose understanding
of the content is aided by being able to view the complete image.</li>
<li><strong>Examples of Success Criterion 1.8.3:</strong>
<ul>
<li>A viewport is used to display an image depicting an organization
chart. A user with a learning disability has difficulty maintaining a
mental representation of the organizational linkages for items out of
view. In order to facilitate their understanding of the organization,
the user drags the sizing icon on the corners of the viewport to allow
the entire chart to be displayed.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-184">1.8.4 Scrollbars:</h4><p class="sc-text">Graphical viewports include scrollbars if the rendered content
(including after user preferences have been applied) extends beyond the
viewport dimensions, <a class="dfn-instance" href="#def-override"
title="definition: Override">overriding</a> any values specified by the
author. <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.4:</strong> <br />
When rendered content exceeds the horizontal or vertical bounds of
a graphical viewport, scrollbars provide a visible indication that not
all of the rendered content is currently visible within the viewport.
The scrollbars provide indication to users who may not be able to
otherwise recognize that the rendered content is not fully visible. </li>
<li><strong>Examples of Success Criterion 1.8.4:</strong>
<ul>
<li>A Web site presents a recipe within a viewport, and the length of the
recipe exceeds the vertical and horizontal dimension of the viewport,
though the step by step graphical depiction of the recipe does not
make this obvious. A user following the recipe, uses the scroll bar to
recognize that additional steps may be present, and scrolls them into
view.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-185">1.8.5 Viewport History:</h4><p class="sc-text"> For user agents that implement a viewport history mechanism (e.g. "back" button), the user can return to any state in the viewport history, restoring the prior point of regard, input focus and selection.<span class="level">(Level A)</span></p>
<br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-186">1.8.6 Open on Request: </h4><p class="sc-text">The user can specify whether or not <a
href="#def-viewport-toplevel">top-level</a> <a
href="#def-viewport-toplevel">viewports</a> (e.g. windows or tabs) open only with an explicit user request or confirmation. (Level A)</p>
<br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-187">1.8.7 Do Not Take Focus:</h4><p class="sc-text">If new <a
href="#def-viewport-toplevel">top-level viewports</a> (e.g. windows or tabs) are configured to open without explicit user request, the user can specify whether or not top-level viewports take the active <a class="dfn-instance" href="#def-keyboard-focus"
title="definition: keyboard focus">keyboard focus</a> when they open. <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criteria 1.8.5, 1.8.6 & 1.8.7:</strong> <br />
Unexpected focus and viewport changes can be disorienting for all users, requiring time and effort for the user to orient to the change. These success criteria are intended to allow the user to be in control of when viewport changes happen so the user can orient to the changes in a predictable fashion.</li>
<li><strong>Examples of Success Criteria 1.8.5, 1.8.6 & 1.8.7:</strong>
<ul>
<li>A web page is loaded in the browser that triggers a secondary page (typically known as a pop-up) to open. The user agent presents the user with the initial page requested and an alert that additional content is available. The user can choose to have this pop-up content shown or not, remaining in control of what is displayed in the user agent's viewport. A user agent may also be configured so that pop-ups do open automatically because the user has chosen to automatically have this content available. The user has a setting however to configure pop-ups such that they open in the background. Hence when visiting a web page with this secondary content, focus remains in the primary viewport with the initial page content requested. The user agent alerts the user that secondary content is available in another viewport and the user can activate this viewport on request, perhaps with a click on the notification mechanism.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criteria 1.8.5, 1.8.6 & 1.8.7:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-189">1.8.9 Close Viewport: </h4><p class="sc-text">The
user can close any <a
href="#def-viewport-toplevel">top-level viewports</a> (e.g. windows or tabs) . <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.9:</strong> <br />
Put the user in control of what viewports the user agent has opened. This reduces distractions from undesired viewports being opened for the user.</li>
<li><strong>Examples of Success Criterion 1.8.9:</strong>
<ul>
<li class="editor-notes">@@ Editors' Note: Add example of "An advertisement opens which has no close button". @@</li>
<li>A user has multiple viewports open such as from a user agent that supports tabbed browsing and is finished viewing content in one or many of them. The user activates a close button on the viewports that are to be closed and they are closed by the user agent. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.9:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-1810">1.8.10 Same UI:</h4><p class="sc-text"> The user can specify that all <a
href="#def-viewport-toplevel">top-level viewports</a> (e.g. windows or tabs) follow the current user interface configuration. <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.10:</strong> <br />
Users orient themselves to a browsing environment with a variety of techniques. This success criteria is designed to ensure that the user does not have to learn multiple strategies to use the browsing viewport.</li>
<li><strong>Examples of Success Criterion 1.8.10:</strong>
<ul>
<li>An individual using magnification software may know that web content begins one inch from the top of the screen in the user agent and has magnification software configured to present content starting at this location. Offering the ability to have all viewports open with the same user interface means the user can quickly focus on the web content of interest without having to orient to different UI configurations each time a viewport opens.</li>
<li class="editor-notes">@@ Editors' Note: Add example of a user with cognitive issues wanting a limited UI and configures it once, and wants all spawned windows to follow that configuration. @@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.10:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-1811">1.8.11 Indicate Viewport Position:</h4><p class="sc-text"> The user can determine the viewport's position relative to the full extent of the <a class="dfn-instance"
href="#def-rendered-content" title="definition: Rendered content">rendered
content</a>. <span class="level">(Level AA)</span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.8.11:</strong> <br />
This criteria targets the ability for a user to easily understand where they are located relative to the total content available for rendering and the amount of content relative to the total being displayed.</li>
<li><strong>Examples of Success Criterion 1.8.11:</strong>
<ul>
<li>A user navigates to a lengthy web page and begins paging through the content. A scroll bar visually indicates the position within the content as the user pages and also that with each paging action only a small portion of the content is being rendered. Another user accesses this web page with a screen reader and has the percentage that the page is scrolled communicated by the screen reader because the user agent makes information from the scroll bar available programmatically.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.8.11:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-focus-mechanism"
id="gl-focus-mechanism"></a><span class="techs-only">Implementing </span>Guideline 1.9 - Provide an effective focus
mechanism.
</h3>
<p class="summary" id="summary19"><strong>Summary</strong>:
Understanding and controlling focus is key to successful interaction with a user agent and its content. The overall purpose of Guideline 1.9 is to ensure that the user can reliably identify the focus location. Additional guidance on focus can be found in Guidelines 2.1, 2.2, 2.3, 2.5, 3.4, 4.1 and 4.2.</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-191">1.9.1 User Interface Focus:</h4><p class="sc-text">An <a class="dfn-instance" href="#def-active-input-focus"
title="definition: active input focus">active input focus</a> is
provided. <span class="level"><span class="level">(Level A)</span> </span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.9.1:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 1.9.1:</strong>
<ul>
<li>A user agent has several menus, toolbars and other controls. As the user presses a key to move to each item on one of the toolbars, the fact that this toolbar item is the active control is made clear through a focus rectangle. When the user switches to a menu, highlighting indicates the active menu element.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.9.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-192">1.9.2 Extensions Focusable:</h4><p class="sc-text">The <a class="dfn-instance" href="#def-keyboard-focus"
title="definition: keyboard focus">keyboard focus</a> can navigate within extensions to the user
interface. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.9.2:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 1.9.2:</strong>
<ul>
<li> A developer creates an extension to a user agent that allows the user to add notes about each web page being visited. A user can press a key to move focus to the user interface of this extension and interact with the functionality offered by the extension. Similarly, the user presses another key to move focus back to the main viewport for the user agent.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.9.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-193">1.9.3 Retrieve Focus: </h4>
<p class="sc-text"> At
any time, the user agent can retrieve <a class="dfn-instance" href="#def-input-focus"
title="definition: input focus">input focus</a> from a nested viewport
(including nested viewports that are user agents). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.9.3:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 1.9.3:</strong>
<ul>
<li>
<span class="proposed-text">A .</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.9.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-194">1.9.4 Return Focus:</h4>
<p class="sc-text">Embedded user agents must support a mechanism for returning <a class="dfn-instance" href="#def-active-input-focus"
title="definition: active input focus">active input focus</a> to the base user agent. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.9.4:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 1.9.4:</strong>
<ul>
<li>
<span class="proposed-text">A .</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.9.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-alternative-views" id="gl-alternative-views"></a>
<span class="techs-only">Implementing </span>
Guideline 1.10 - Provide alternative views.
</h3>
<p class="summary" id="summary110"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-1101">1.10.1 Text View:</h4><p class="sc-text"> The user can view all <a
class="dfn-instance" href="#def-text-source"
title="definition: text source">text source</a> that is available to the user agent. <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.10.1:</strong> <br />
The source view is the ultimate fallback when the browser cannot
properly render some content, or when the user cannot take advantage of
the content as rendered or using the mechanisms provided.</li>
<li><strong>Examples of Success Criterion 1.10.1:</strong>
<ul>
<li>When the content author failed to provide alt text or longdesc for an
image, the user can, as a last resort, try to get some information by
examining the source to see the image's URI, class, and similar attributes.</li>
<li>When the user wants to create a customized style sheet for a Web site,
they need to identify the style, class, and id attributes it uses. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.10.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-1102">1.10.2 Outline View:</h4><p class="sc-text"> An
"outline" view of <a class="dfn-instance" href="#def-rendered-content"
title="definition: Rendered content">rendered content</a> is provided,
composed of labels for important structural elements (e.g. heading text,
table titles, form titles, and other labels that are part of the content).
<span class="level">(Level AA)</span> </p>
<p class="sc-note" id="note-1102"><strong>Note:</strong> The outline constitutes the important structural elements for the user (See 1.10.3). A label is defined by each markup
language specification. For example, in HTML, a heading
(<code>H1</code>-<code>H6</code>) is a label for the section that follows it,
a <code>CAPTION</code> is a label for a table, and the <code>title</code> attribute is a label for its element. </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.10.2:</strong> <br />
Outline views can help all users get a simplified view or overview of a
document. They are particularly useful for users with memory or
cognitive disabilities, as well as users with serial access to content
or who navigate sequentially. The outline view is a type of summary view
and should reduce orientation time. A navigable outline view will add
further benefits for these users.</li>
<li><strong>Examples of Success Criterion 1.10.2:</strong>
<ul>
<li>A Web browser provides an optional panel displaying a hierarchical list
of the headers and tables in the current document.
The user is able to expand or shrink portions of the outline view for
faster access to important parts of content.</li>
<li>A Web browser provides a command to use CSS display and visibility
properties to hide all content other than important structural elements
such as titles, headings, and table headings. </li>
<li>A Web browser provides a structured view of form controls (e.g. those
grouped by LEGEND or OPTGROUP in HTML) along with their labels. </li>
<li>Amaya table of contents view <span class="editor-notes">@@ Editors' Note: Insert photo@@</span><br />
This image shows the table of contents view provided by Amaya [AMAYA].
This view is coordinated with the main view so that users may navigate
in one viewport and the focus follows in the other. An entry in the
table of contents with a target icon means that the heading in the
document has an associated anchor. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.10.2:</strong>
<ul>
<li>This Success Criterion (1.10.2) deals with making document structure
perceivable to the user. It is complimentary to Guideline 4.7 which
deals with making document structure navigable.</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-1103">1.10.3 Configure Set of Important
Elements:</h4><p class="sc-text"> The user can configure the set of important elements for the hierarchical view, including by element type (e.g. headers). <span class="level">(Level AAA)</span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.10.3:</strong> <br />
Sometimes authors will visually convey relationships between elements by spatially grouping them, by giving them the same coloration or background, and so forth. Users may not be able to perceive those attributes, such as when using a screen reader, or when strong magnification makes it difficult to make a mental model of the screen layout. In those cases the user agent can assist by providing a view of the data that groups elements that that user agent perceives as implying relationships. </li>
<li><strong>Examples of Success Criterion 1.10.3:</strong>
<ul>
<li>
<span class="proposed-text">To be written</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.10.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-info-link" id="gl-info-link"></a>
<span class="techs-only">Implementing </span>
Guideline 1.11 - Provide element information.
</h3>
<p class="summary" id="summary111"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-1111">1.11.1 Access Relationships:</h4>
<p class="sc-text"> The user can access explicitly-defined relationships based on the user's position in content (e.g. show form control's label, show label's form control, show a cell's table headers). <span class="level">(Level A)</span> :</p>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.11.1:</strong> <br />
Some users have difficulty perceiving, remembering, or understand the relationships between elements and their contexts. HTML controls and elements are sometimes grouped together to make up a composite control; certain elements relate to others in a recognizable manner, such as relationships with 'id' attributes and child elements. This is the case with Ajax widgets and with form elements. By making sure the user can be informed about these relationships means that, say, visually disabled users can better understand these relationships even if the elements are not adjacent on the screen or the DOM. </li>
<li><strong>Examples of Success Criterion 1.11.1:</strong>
<ul>
<li>John has low vision and uses a screen magnifier to access his Browser. When interacting with tables and spreadsheets John has to move the viewport of the magnifier to understand the row and column titles of the cell with which he is interacting. This takes additional time and effort and is therefore frustrating. John has just purchased a new Browser because it presents the row and column titles when he hovers over a cell - this makes him much more productive at his accounting job. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.11.1:</strong>
<ul>
<li>WAI-ARIA</li>
<li>UAAG 2.7.3 Location in Hierarchy</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-1112">1.11.2 Extended Link
Information:</h4>
<p class="sc-text"> The user agent provides for each link:
<span class="level">(Level AAA)</span> :</p>
<ul class="d">
<li><strong class="handle">link title</strong></li>
<li><strong class="handle">technology type</strong> (of the linked <a
class="dfn-instance" href="#def-web-resource"
title="definition: Web resource">Web resource</a>)</li>
<li><strong class="handle">internal/external: </strong> (whether the link
is internal to the resource e.g. the link is to a target in the same
Web page)</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 1.11.2:</strong> <br />
<span class="proposed-text">Users who use screen readers need to be able to easily discover information about a link, including the title of the link, whether or not that link is a web page, PDF etc. and whether the link goes to a new page or a different location in the current page, in order to navigate Web content more quickly and easily.</span></li>
<li><strong>Examples of Success Criterion 1.11.2:</strong>
<ul>
<li>
<span class="proposed-text">Robert, who uses a screen reader, needs to know whether a given link will automatically open in a new page or a new window. The browser indicates this information so he can discover it before he makes a decision to click on a link.</span></li>
<li class="proposed-text">Maria has an attention disorder, new windows opening are a large distraction. She needs to know whether a given link will automatically open in a new page or a new window. The browser indicates this information so she can decide not to follow a link that opens a new window.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 1.11.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h2 class="principle"><a name="principle-operable"
id="principle-operable"></a>PRINCIPLE 2<a name="gl-keyboard-access"
id="gl-keyboard-access2"></a>. Ensure that the user interface is
operable</h2>
<h3 class="guideline"><a name="gl-keyboard-access"
id="gl-keyboard-access"><span class="techs-only">Implementing </span>Guideline 2.1</a> - Ensure full keyboard access.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-keyboard-access">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary21"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-211">2.1.1 Keyboard Operation</h4><p class="sc-text">: All
functionality can be operated via the keyboard using sequential or direct
keyboard commands that do not require specific timings for individual
keystrokes, except where the underlying function requires input that depends
on the path of the user's movement and not just the endpoints (e.g. free
hand drawing). This does not forbid and should not discourage providing mouse
input or other input methods in addition to keyboard operation. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.1:</strong> <br />
A user should be able to navigate, read and use all of the web page or application without needing to use a mouse. Some users do not use a mouse, others can only use a pointing device that uses the keyboard API. Therefore, ensure that the user can interact with enabled components, select content, navigate viewports, configure the user agent, access documentation, install the user agent, and operate user interface controls, all entirely through keyboard input.
<br />User agents generally support at least three types of keyboard operation:
<ul><li>1. Direct (e.g. keyboard shortcuts such a "F1" to open the help menu; see checkpoint 11.4 for single-key access requirements),</li>
<li>2. Sequential (e.g. navigation through cascading menus), and </li>
<li>3. Spatial (e.g. when the keyboard is used to move the pointing device in two-dimensional visual space to manipulate a bitmap image). </li></ul><br />
User agents should support direct or sequential keyboard operation for all functionalities. Furthermore, the user agent should satisfy this checkpoint by offering a combination of keyboard-operable user interface controls (e.g. keyboard operable print menus and settings) and direct keyboard shortcuts (e.g. to print the current page). </li>
<li><strong>Examples of Success Criterion 2.1.1 :</strong>
<ul>
<li>The user must be able to do the following through the keyboard alone (or pointing device alone or voice alone):
<ul><li>Select content and operate on it. For example, if the user can select rendered text with the mouse and make it the content of a new link by pushing a button, they also need to be able to do so through the keyboard and other supported devices. Other operations include cut, copy, and paste.</li>
<li>Set the focus on viewports and on enabled elements.</li>
<li>Install, configure, uninstall, and update the user agent software.</li>
<li>Use the graphical user interface menus. Some users may wish to use the graphical user interface even if they cannot use or do not wish to use the pointing device.</li>
<li>Fill out forms.</li>
<li>Access documentation.</li>
</ul>
</li>
<li>An author uses the CSS overflow property to constrain the size of a block of content. The user agent provides scroll bars to display text that overflows the container. The user can use the keyboard to enter the element and operate the scrollbars to visually access the content. The user can return to the main flow of the next element on the page (see SC 2.1.3) </li>
<li>The author codes a volume control slider widget. The user can focus on the widget, and using the arrow keys to increase or decrease the volume, and then hit another key to move to the next element in the content. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.1:</strong>
<ul>
<li>Microsoft Keyboard accessibility document</li>
<li>Apple keyboard</li>
<li>Unix</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-212">2.1.2 Keyboard Focus<span class="diff-renumber"> (former 1.9.1)</span>: </h4>
<p class="sc-text">Every <a class="dfn-instance" href="#def-viewport" title="definition: viewport">viewport</a>
has an active or inactive <a class="dfn-instance" href="#def-keyboard-focus" title="definition: keyboard focus">keyboard focus</a> at all times. <span class="level"><span class="level">(Level A)</span> </span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.2:</strong> <br />
Both the user and some types of assistive technology need to know what will be affected by any keyboard input, so it's important that they be able to tell which window, viewport, and controls have the keyboard focus at any time. This applies whether window and viewport are active (active keyboard focus) or inactive (inactive keyboard focus). Even when a window is inactive, it can be affected by simulated keyboard input sent by assistive technology tools. Active keyboard focus is indicated to the user by focus cursors and text cursors, as required by Guidelines 1.3, and made available to assistive technology, as required by Success Criterion 4.1.6.
</li>
<li><strong>Examples of Success Criterion 2.1.2:</strong>
<ul>
<li>Alan launches a web browser and navigates to a web page. Initially the keyboard focus is treated as being on the entire document, and that is exposed to assistive technology, but there is no visible cursor. When he presses the tab key, the focus moves to the first link on the web page, and a cursor in the form of a dotted rectangle appears around that link. </li>
<li>Ellen launches a web browser and navigates to a web page that has an enabled edit field. The browser places the keyboard focus on the edit field, so she can immediately start entering text, and it's location is shown using a text cursor (usually a vertical line or i-beam). As Ellen types, the text cursor moves to show where the next character will appear. If she activates another window, the browser may hide the cursor in the now inactive window, but its location is still available to assistive technology. </li>
<li>Raymond has low vision. As the keyboard focus moves from one control to another, or one window to another, his screen enlarger utility detects the focus change and pans its viewport to keep the focus location visible. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.2:</strong>
<ul>
<li>Guideline 1.3 (Provide highlighting for selection, active keyboard focus, enabled elements, visited links) ensures that the focus location is made visible to users. </li>
<li>Success Criterion 4.1.6 (Properties) ensures that the focus location is available to assistive technology. </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-213">2.1.3 Viewport Navigation<span class="diff-renumber"> (former 1.9.2 & 1.9.4)</span>: </h4>
<p class="sc-text">The user can move the active <a class="dfn-instance" href="#def-keyboard-focus"
title="definition: keyboard focus">keyboard focus</a> to any <a class="dfn-instance" href="#def-viewport" title="definition: viewport">viewport</a>. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.3:</strong> <br />
Each viewport has a keyboard focus (per 2.1.2), but it's also important that the user be able to navigate to that viewport, making its keyboard focus become the active keyboard focus. This navigation can be between viewports within the application, or between windows or applications. This includes the user agent's user interface, extensions to the user interface (e.g. add-on), content, and plug-ins handling content. </li>
<li><strong>Examples of Success Criterion 2.1.3:</strong>
<ul>
<li>Ruth is working in her web browser, where one document window (viewport) is active (has the active keyboard focus). When she switches to her word processor, the web browser's window and its keyboard focus become inactive, and it hides its cursor. When she switches back to the browser window, it reactivates that viewport, its keyboard focus becomes active again, and its cursor reappears in the same location as when she switched to a different application. </li>
<li>A developer creates an extension to a user agent that allows the user to add notes about each web page being visited. A user can press a shortcut key to move focus to the user interface of this extension and interact with the functionality offered by the extension. Similarly, the user presses another key to move focus back to the main viewport for the user agent in the same location as when she moved to the plugin. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.3:</strong>
<ul>
<li>2.2.1 ensures that the user can navigate to elements within the viewport.</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-214">2.1.4 Specify preferred keystrokes:<span class="diff-renumber"> (former 2.1.2)</span></h4>
<p class="sc-text">: The user can override any keyboard shortcut including recognized author supplied shortcuts (e.g. accesskeys) and user interface controls, except for conventional bindings for the operating environment (e.g. arrow keys for navigating within menus). <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.4:</strong> <br />
Some users may be able to hit certain keys on the keyboard with greater ease than others. Assistive technology software typically has extensive keyboard commands as well. The goal of this SC is to enable the user to be in control of what happens when a given key is pressed and use the keyboard commands that meet his or her needs.<br />
</li>
<li><strong>Examples of Success Criterion 2.1.4:</strong>
<ul>
<li>Laura types with one hand and finds keys on the left side of the keyboard easier to press. She browses to a web page and notices that the author has assigned access keys using keys from the right side of the keyboard. She opens a dialog in the user agent and reassigns the access keys from the web page to the left side of the keyboard home row. </li>
<li>Elaine's screen magnification program uses alt+m to increase the size of the magnified area of the screen. She notices that in her web browser, alt+m is a hotkey for activating a home button that stops her from being able to control her magnification software. She opens a hotkey reassignment feature in the user agent, and sets alt+o to be the new hotkey for the home button. Her screen magnification software now works correctly.<br />
</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-215">2.1.5 No Keyboard Trap<span class="diff-renumber"> (former 2.1.3)</span></h4>
<p class="sc-text">: The user
agent prevents keyboard traps as follows: <span class="level">(Level A)</span></p>
<ul>
<li><strong class="handle">(a) in the UI</strong>: if keyboard focus can be
moved to a component using the keyboard, then focus can be moved away
from that component using standard sequential keyboard commands (e.g.
TAB key) </li>
<li><strong class="handle">(b) in the rendered content</strong>: provides a
documented direct keyboard command that will always restore keyboard
focus to a known location (e.g. the address bar). </li>
<li><strong class="handle">(c) in the rendered content:</strong> provides a
documented direct keyboard command that will always move keyboard focus
to a subsequent focusable element</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.5:</strong> <br />
Intent: If the user can put focus on an element, that they can remove focus and move on to the next element. This is often a problem with embedded objects. The user agent needs to provide a way to always return to the previous or next element in the content, or a known location, such as the address bar. The user agent also needs to be able to take control back from the embedded object, no matter what it is. <br />
</li>
<li><strong>Examples of Success Criterion 2.1.5:</strong>
<ol type="a">
<li>The user can press tab to put focus on an embedded object and can press shift-tab to move focus to the previous object and tab to move focus to the next object.</li>
<li>The user has moved the focus to a toolbar extension that does not relinquish control back to the user agent. The user can press Alt-D to move focus to the address bar. </li>
<li>The user has moved the focus to an embedded scripted application that was poorly programmed. the user can press alt-N (or any documented key combination) that overrides the scripting and moves the focus to the next element in the content. </li>
</ol>
</li>
<li><strong>Related Resources for Success Criterion 2.1.5:</strong>
<ul>
<li>Compound documents </li>
<li>Other SC in UAAG. </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-216">2.1.6 Separate Selection from
Activation:<span class="diff-renumber"> (former 2.1.4)</span></h4><p class="sc-text"> The user can specify that selection is separate from activation (e.g. navigating through a set of radio buttons without changing
which is the active/selected option). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.6:</strong> <br />
This is a repair function for when an author violates WCAG, but the user still needs to be able to read a page without necessarily activating any controls. <br />
</li>
<li><strong>Examples of Success Criterion 2.1.6:</strong>
<ul>
<li>when a user opens a drop down menu from the keyboard, they must be able to use the arrow keys to move up and down the list, without triggering an action from the items they are moving past. </li>
<li>A list of radio buttons where putting the focus on the radio button to read it causes the radio button to be selected. The user should be able to arrow or tab through the list of radio buttons without causing any one to be selected. Selection is a separate discrete operation like spacebar. This overrides any author provided scripting behavior.
<br />
</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.6:</strong>
<ul>
<li>ARIA</li>
<li>WCAG</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-217">2.1.7
Follow Text Keyboard Conventions<span class="diff-renumber"> (former 2.1.5)</span></h4>
<p class="sc-text">: Views that render text support the standard text area
conventions for the <a class="termdef" href="#def-operating-environment" title="definition: operating environment">operating environment</a>, such as
character keys, Backspace/Delete, Insert, arrow key navigation (e.g.
caret browsing), Page Up/Page Down, navigate to start/end, navigate by
paragraph, shift-to-select mechanism. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.7:</strong> <br />
Providing a full set of keyboard inputs allows users to efficiently - or at all - perform necessary tasks. Making these inputs consistent within and across programs greatly reduces learning curve, cognitive load, and errors. </li>
<li><strong>Examples of Success Criterion 2.1.7:</strong>
<ul>
<li>Directional keys, letter keys, and the Enter key function should allow navigation within and activation of drop-down menus.</li>
<li>Ctrl+C or Command+C should copy selected text to the clipboard, allowing the user to avoid manually retyping, and possibly needing to memorize, large amounts of data.<br />
<span class="editor-notes">@@ Editors' Note: comment - what happens when things are not consistent. closing dialog boxes are inconsistent ESC or ALT-F4, might be text area keyboard conventions/controls, not just navigation. @@</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.7:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-218">2.1.8
Make Important Command Functions Efficient<span class="diff-renumber"> (former 2.1.9)</span></h4>
<p class="sc-text">: Important command functions (e.g. related to navigation, display, content, information management) are more efficient than sequential keyboard navigation. <span class="level">(Level AA)</span></p>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.8
:</strong> <br />
Let the user access commonly used functions as efficiently as possible. Efficient keyboard navigation is especially important for people who cannot easily use a mouse.</li>
<li><strong>Examples of Success Criterion 2.1.8:</strong>
<ul>
<li> The user can open a document by pressing Ctrl+O or Command+O. </li>
<li>The user can temporarily enlarge the rendered content by pressing Ctrl+Plus, rather than having to invoke a menu, choose a command to display a dialog box, select a tab, etc.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.8:</strong>
<ul>
<li>Links to 1.1. <span class="principle">Comply with applicable
specifications and conventions</span></li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-219">2.1.9
Allow Override of User Interface Keyboard Commands<span class="diff-renumber"> (former 2.1.10)</span>:</h4>
<p class="sc-text">
The user can override any keyboard shortcut binding for the user agent user
interface except for conventional bindings for the operating environment
(e.g. access to help). The rebinding options must include single-key and
key-plus-modifier keys if available in the operating environment. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.1.9:</strong> <br />
The intent of this success criterion is to ensure that people using a keyboard interface have the ability to remap the user agent's keyboard shortcuts in order to avoid keystroke conflicts with assistive technology, reduce number of keystrokes, use familiar keystroke combinations, and optimize keyboard layout (e.g. for one-handed use). This is important for people with dexterity issues where every keystroke can be time consuming, tiring or painful. It is also important for people using assistive technologies such as screen readers, where many keystrokes are already in use by the assistive technology. </li>
<li><strong>Examples of Success Criterion 2.1.9:</strong>
<ul>
<li>Ctrl+f may be a command in a screen reader to read the item with focus and this is also typically a user agent find command. The user agent should allow the user to reassign the find command to a non-conflicting key binding. To allow this level of user control, the user agent could provide a list of user interface features and default keyboard assignments with options for the user to assign new key combinations. User keyboard customizations should be saved similar to other user preferences by the user agent.</li>
<li>Jim, a one handed keyboardist, needs to map all keys to the left side of the keyboard in order to quickly and comfortably reach the keyboard shortcuts he uses frequently.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.1.9:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-sequential-navigation"
id="gl-sequential-navigation"></a><span class="techs-only">Implementing </span>Guideline 2.2 - Provide sequential navigation <span class="diff-renumber">[new, includes former 2.1.8 and 1.9.8, and a new SC]</span>
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-sequential-navigation">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary22"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-221">2.2.1 Sequential Navigation Between Elements <span class="diff-renumber">[replaces 1.9.8 Bi-Directional and 2.1.8 Keyboard Navigation] </span></h4>
<p class="sc-text">The user can move the keyboard focus backwards and forwards through all recognized enabled elements in the current viewport. (Level A) </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.2.1:</strong> <br />
Sequential keyboard navigation is the most fundamental, universal method of keyboard access. While it can be slower and require more input than other methods (such as direct, structural, or search-based navigation) it is a simpler mechanism that requires very little cognitive load or memorization, and is more consistent across contexts. Users need keyboard access to all viewports and all enabled elements so that they can manipulate them, view them with screen magnifiers, or have them described by screen readers. The ability to move both forward and backward through the navigation order greatly reduces the number of keystrokes and allows the user to more easily recover from mistakes in overshooting a destination. </li>
<li><strong>Examples of Success Criterion 2.2.1:</strong>
<ul>
<li>Sooj cannot use a pointing device, so she moves the keyboard focus to the next enabled element by pressing the Tab key, and to the previous enabled element by pressing Shift+Tab. Within list boxes and radio button groups she uses the up and down arrow keys to move to the next and previous items. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.2.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-222">2.2.2 Sequential Navigation Between Viewports<span class="diff-renumber"> [new]</span>:</h4>
<p class="sc-text">The user can move the keyboard focus backwards and forwards between viewports, without having to sequentially navigate all the elements in a viewport. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.2.2:</strong> <br />
It is important for the user to be able to jump directly to the next or previous viewports without having to visit every element in a viewport on the way to the next viewport, because that can add an exorbitant number of navigation commands to operations that should be both easy and efficient.User need keyboard access to all viewports and all enabled elements so that they can manipulate them, view them with screen magnifiers, or have them described by screen readers. The ability to move both forward and backward through the navigation order greatly reduces the number of keystrokes and allows the user to more easily recover from mistakes in overshooting a destination.</li>
<li><strong>Examples of Success Criterion 2.2.2:</strong>
<ul>
<li>Sooj cannot use a pointing device, so she moves the keyboard focus to the next pane by pressing F6 or the previous pane by pressing Shift+F6. She moves between tabbed document views by pressing Ctrl+Tab and Shift+Ctrl+Tab. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.2.2:</strong>
<ul>
<li>See the description of 2.2.1 for background information on the importance of sequential navigation. </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-223">2.2.3 Default Navigation Order:<span class="diff-renumber"> (former 1.9.9) </span></h4>
<p class="sc-text">If the author has not specified a navigation order, the default is
<a class="dfn-instance" href="#def-sequential-navigation"
title="definition: sequential navigation">sequential navigation</a>, in
document order. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.2.3:</strong> <br />
The reason for this success criteria is that browsers will be consistent on the tab order they provide WHEN the content author didn't explicitly define one.It is important for users to have a mental map of where the focus will land when they press the Tab key or use other sequential navigation commands. If the focus jumps in seemingly random fashion, skipping up and down, it becomes impossible to use this method efficiently. It requires the user to stop, find the focus, reorient, and determine whether and in which direction they should proceed every single time they press a navigation key. This is a particular problem for users with some cognitive limitations or whose disability makes input difficult, tiring, or painful. Content authors are expected to define a logical navigation order in their documents, but if they have not specified one, this success criterion ensures the order will at least be consistent between user agents. </li>
<li><strong>Examples of Success Criterion 2.2.3:</strong>
<ul>
<li>Alec is filling out an HTML form. Because the form's author has not specified a navigation order using the tabindex attribute, when Alec presses the Tab key the focus moves to the next control in the order they are defined in the underlying HTML. This order is likely to seem logical as long as the author is not using styles to change the order in which which the controls appear on page, but even if that is not the case, Alec will still experience the same order when using different browsers on different computers, and therefore navigating the page can become an accustomed habit and much easier than if the order were to change from one system to the other. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.2.3:</strong>
<ul>
<li>See Web Content Accessibility Guidelines 2.0 success criterion 2.4.3 Focus Order: If a Web page can be navigated sequentially and the navigation sequences affect meaning or operation, focusable components receive focus in an order that preserves meaning and operability. </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-224">2.2.4 Options for Wrapping in Navigation:<span class="diff-renumber"> (new) </span></h4>
<p class="sc-text">The user can have sequential navigation prevent wrapping or can receive feedback when wrapping. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.2.4:</strong> <br />
Users need a good mental map of the navigation sequence and behavior, and particularly need to know when they have started over again so they can maintain that mental map and not waste time and energy inadvertently revisiting information. This is a greater problem for users who can only perceive a limited region (e.g. having a narrow field of vision, or using a screen magnifier or screen reader) or have limited short-term memory. This also prevents people with mobility issues from having to use extra navigation commands. </li>
<li><strong>Examples of Success Criterion 2.2.4:</strong>
<ul>
<li>Betsy is using a screen magnifier that only shows her a single line of text. She's navigating through a long list of unsorted items in a list box, searching for one particular entry which, it turns out, is not in the list. Each time she presses the down arrow she is presented with the next item in the list. This particular list box wraps, so when she has read the final entry and presses the down arrow, she is once again presented with the first entry in the list. Unfortunately, because she is quickly discounting every entry that is not her intended goal, she hasn't memorized the list, and it takes her a long time to realize that she's scrolling through the same set of items again and again. To avoid having this happen again, she can turn on options to prevent wrapping, or have the user agent play a sound or present a message before or as it wraps back to the first item. However, keyboard users who can see the entire screen may very well benefit from having wrapping without being interrupted by a pop-up dialog box, so ideally this behavior should be under the user's control. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.2.3:</strong>
<ul>
<li>N/A</li>
</ul>
</li>
</ul>
<h3 class="guideline"><a name="gl-direct-navigation-and-activation"
id="gl-direct-navigation-and-activation"></a><span class="techs-only">Implementing </span>Guideline 2.3 - Provide direct navigation and activation<span class="diff-renumber"> [includes former 2.1.6, 2.1.7, 2.1.11]</span>
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-direct-navigation-and-activation">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary23"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-231">2.3.1 Direct Navigation to Important Elements:<span class="diff-renumber"> (former 2.7.4)</span></h4>
<p class="sc-text">The user can navigate directly to important (structural and operable) elements in rendered content. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.3.1
:</strong> <br />
It is often difficult for some people to use a pointing device (the standard method of direct navigation) to move the viewport and focus to important elements. In this case some other form of direct navigation - such as numbers or key combinations assigned to important elements - should be available which can then be accessed via the keyboard or speech control technology. </li>
<li><strong>Examples of Success Criterion 2.3.1
:</strong>
<ul>
<li>Mary cannot use the mouse or keyboard due to a repetitive strain injury, instead she uses voice control technology with uses a mouse-less browsing plug-in to her browser. The plug-in overlays each hyperlink with a number that can then be used to directly select it (e.g. by speaking the command "select link 12"). This prevents Mary from having to say the word 'tab' numerous times to get to her desired hyperlink. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.3.1
:</strong>
<ul>
<li>2.7.7 configure set of important elements <span class="editor-notes">@@ Editor's Note - is this still the right number?@@</span></li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-232">2.3.2
Present Direct Commands in Rendered Content<span class="diff-renumber"> (former 2.1.6)</span>:</h4>
<p class="sc-text"> The user can have any recognized direct commands (e.g. accesskey) in rendered content be presented with their associated elements. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.3.2:</strong> <br />
Make it easy to for users to discover or be reminded of keyboard shortcuts and similar commands without leaving the context in which they're working. Easy keyboard access is especially important for people who cannot easily use a mouse. An example of this is mouseless browsing. Some users have problems controlling the mouse and/or the keyboard. Therefore users often find control by speech recognition to be advantageous. In this case it is much more efficient for navigation and activation selection points to be both viewable by the user and controllable by their assistive technology. </li>
<li><strong>Examples of Success Criterion 2.3.2:</strong>
<ul>
<li> "[Ctrl+t]" displayed after a link whose accesskey value is "t".</li>
<li>An audio browser reading the value or label of a form control followed by "accesskey control plus t").</li>
<li>Mary cannot use the mouse or keyboard due to a repetitive strain injury, instead she uses voice control technology with uses a mouse-less browsing plug-in to her browser. The plug-in overlays each hyperlink with a number that can then be used to directly select it (e.g. by speaking the command "select link 12"). This prevents Mary from having to say the word 'tab' numerous times to get to her desired hyperlink. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.3.2:</strong>
<ul>
<li> See 2.1.7 for User Interface commands </li>
<li> Mouseless Browsing Firefox Extension: <a href="https://addons.mozilla.org/en-us/firefox/addon/mouseless-browsing/" title="https://addons.mozilla.org/en-us/firefox/addon/mouseless-browsing/">https://addons.mozilla.org/en-us/firefox/addon/mouseless-browsing/</a> </li>
<li> Perceivable navigation and activation keys: <a href="http://www.mouseless.de/index.php?/content/view/17/30/" title="http://www.mouseless.de/index.php?/content/view/17/30/">http://www.mouseless.de/index.php?/content/view/17/30/</a> </li>
<li> Microsoft placing Wikipedia on TV-DVD and using mouseless browsing via remote control: <a href="http://research.microsoft.com/research/tem" title="http://research.microsoft.com/research/tem">http://research.microsoft.com/research/tem</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-233">2.3.3 Direct activation<span class="diff-renumber"> (former 2.7.6)</span></h4>
<p class="sc-text">: The user can move directly to and activate any operable
elements in rendered content. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.3.3 :</strong> <br />
It is often difficult for some people to use a pointing device (the standard method of direct navigation) to move the viewport and focus to important elements. In this case some other form of direct navigation - such as numbers or key combinations assigned to important elements - should be available which can then be accessed via the keyboard or speech control technology. </li>
<li><strong>Examples of Success Criterion 2.3.3 :</strong>
<ul>
<li>Mary cannot use the mouse or keyboard due to a repetitive strain injury, instead she uses voice control technology with uses a mouse-less browsing plug-in to her browser. The plug-in overlays each hyperlink with a number that can then be used to directly select it (e.g. by speaking the command "select link 12"). This prevents Mary from having to say the word 'tab' numerous times to get to her desired hyperlink. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.3.3:</strong>
<ul>
<li>2.7.7 configure set of important elements <span class="editor-notes">@@ Editor's Note - is this still the right number?@@</span></li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-234">2.3.4 Present Direct Commands in User Interface<span class="diff-renumber"> (former 2.1.7)</span>:</h4>
<p class="sc-text"> The user can have any direct commands (e.g. keyboard shortcuts) in the user agent user interface be presented with their associated user interface controls (e.g. "Ctrl+S" displayed on the "Save" menu item and toolbar button). <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.3.4:</strong> <br />
For many users, including those who use the keyboard or and input method such as speech, the keyboard is often a primary method of user agent control. It is important that direct keyboard commands assigned to user agent functionality be discoverable as the user is exploring the user agent. </li>
<li><strong>Examples of Success Criterion 2.3.4:</strong>
<ul>
<li>The speech input user who sees a button on a toolbar needs to be able to determine that ctrl+p is the keyboard equivalent for activating the print button. If such key assignments are not displayed as part of the user interface by default, a user agent should have an option to alter UI display to include all direct hotkey assignments visually as part of the controls the hotkeys activate.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.3.4:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-235">2.3.5
Allow Override of Accesskeys<span class="diff-renumber"> (former 2.1.11)</span></h4><p class="sc-text">: The
user can override any recognized author supplied content keybinding (i.e. access key). The user must have an option to save the
override of user interface keyboard shortcuts so that the rebinding persists
beyond the current session. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.3.5</strong><br />
Content authors may utilize the Accesskey attribute to define short cut keys which allow quick access to specific elements, actions, or parts of their Web content. The author-selected short cuts may utilize keystrokes that are unique to their site, differing from conventions used, and or familiar, to users of other similar sites, or sites offering similar functionality. Users of assistive technologies who rely upon keyboard input may wish to have a consistent mapping of shortcut keys to similar, or common actions or functions across the sites they visit. <br />
<br />
User agents should allow users to define a preferred key combination for specific instances of author defined accesskeys. The user should have the option to make any defined override to be persistent across browsing sessions. <br />
<br />
User agents may also offer the user the option to automatically apply preferred key combinations for content which has author supplied accesskey bindings, based upon the associated text, label, or ARIA role, and which override any author specified keybinding for that page content. </li>
<li><strong>Examples of Success Criterion 2.3.5</strong>:
<ul>
<li>A speech recognition user has defined standard commands to access commonly used parts of a Web site. For example, speaking the the command "site search" will take the user to a Web site's search function. A site author may assign an access key to set focus to the search input field, basing the accesskey on the first letter of the search engine used (e.g. G for Google or B for Bing, rather than the mnemonic S for search). The speech user has specified an override key mapping of S, which is consistent with the keystroke issued by the speech recognizer they are using. </li>
<li>A mobile device user, whose primary keyboard interface is their phone's numeric keypad, maps common Web site actions to numeric shortcut keys. For example, the user prefers to have the 1 key to activate a site's "skip to content" function. An author of a site visited daily by this user defines "S" as the accesskey for the skip to content function. The user overrides the author defined accesskey of "S" with "1". </li>
<li class="editor-notes">@@ Editors' Note: good place to add i18n example, accesskey - o umlaut, but not on local keyboard@@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.3.5:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h3 class="guideline"><a name="gl-search-text" id="gl-search-text"><span class="techs-only">Implementing </span>Guideline 2.4 <span class="diff-renumber">(former 2.6)</span></a> - Provide text search.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-search-text">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary24"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-241">2.4.1 Find:</h4><p class="sc-text"> The user can perform a search within rendered content (e.g. not hidden with a style), including text alternatives, for any sequence of characters from the <a class="dfn-instance" href="#def-doc-char-set"
title="definition: Document character set">document character set</a>. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.4.1 :</strong> <br />
To provide a function that allows the user to easily locate desired information in rendered or alternative text. Give the option of searching the alternative content. In the case of an embedded user agent, (e.g. media player), the embedded user agent provides the search for its content. <span class="editor-notes">@@ Editors' Note: Is this even necessary? Who does the search in an embedded video player?"@@</span></li>
<li><strong>Examples of Success Criterion 2.4.1 :</strong>
<ul>
<li>A user wants to locate a text string in a long document. The user agent provides a mechanism for entering the desired text string, such as a text box with a search button. </li>
<li>A user wants to search for text in all views of the document, including views of the text source (source view)</li>
<li>A user wants to search the element content of form elements (where applicable) and any label text. </li>
<li class="editor-notes">@@ Editors' Note: searching video captions??@@</li>
<li class="editor-notes">@@ Editors' Note: Searching embedded SVG?@@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.4.1 :</strong>
<ul>
<li>WCAG</li>
<li>2.6.2 ,3,4,5</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-242">2.4.2 Find Direction:</h4><p class="sc-text"> The user can search forward or backward from the focused location in content. The user is notified of changes in search direction. The user is notified when the search reaches the upper or lower extent of the content based on the search direction. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.4.2 :</strong> <br />
Searching in any direction from the current point of focus allows for maximum flexibility in allowing the user to easily locate the text used in the search. Users for who reading is difficult can greatly reduce the amount of reading required to find the information needed. Searching improves navigation efficiency which is especially important for people with dexterity issues where every keystroke can be time consuming, tiring or painful. It is recommended that the user also has the ability to search forward or backward within any selected content. <span class="editor-notes">@@ Editors' Note: needs some explanation. how to keep searching within the selected content</span></li>
<li><strong>Examples of Success Criterion 2.4.2 :</strong>
<ul>
<li>A user has been reading through a web page and wants to quickly locate a phrase previously read. When opening the browser's page search feature, the user has options to search forward and backward from the current location. If the search reaches an endpoint in the document, the user is notified that the search has wrapped around, such as with an alert box or other indication.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.4.2 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-243">2.4.3 Match Found:</h4>
<p class="sc-text"> When there is a match, the user is alerted and the viewport's content moves so that the matched text content is at least partially within it. The user can search for the next instance of the text from the location of the match.
<span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.4.3 :</strong> <br />
It is important for the user to easily recognize where a search will start from. <br />
<span class="editor-notes">@@ Editors' Note: If the caret has been moved, from its new location.@@</span></li>
<li><strong>Examples of Success Criterion 2.4.3 :</strong>
<ul>
<li>Example: Jules is low vision and uses a
magnified screen. She frequently searches for terms that appear
multiple times in a document that contains a lot of repetition. It
is important that the viewport moves and if necessary her screen
scrolls after each search so she can easily track where she is in
the document. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.4.3 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-244">2.4.4 Alert on No Match: </h4><p class="sc-text">The user is
<a href="#def-alert">notified</a> when there is no match or after the last match in content (i.e.
prior to starting the search over from the beginning of content). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.4.4 :</strong> <br />
It is important for users to get clear, timely feedback so they don't waste time waiting or, worse, issue a command based on a wrong assumption. It is important during a search that users are informed when there is no match or that the search has reached the beginning of the document.</li>
<li><strong>Examples of Success Criterion 2.4.4 :</strong>
<ul>
<li>Dennis uses a screen reader. As soon as he gets a message that
there is no match he goes on to search for something else. If he
does not get a message he wastes time retrying the search to make
sure there is not a match.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.4.4 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-245">2.4.5 Advanced Find:</h4><p class="sc-text"> The user agent provides an accessible advanced
search facility, with a case-sensitive and case-insensitive search
option, and the ability for the user to perform a search within all
content (including hidden content and captioning) for text and text
alternatives, for any sequence of characters from the document character
set. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.4.5 :</strong>
Searching is much more useful when the user can specify
whether case matters in a search and when the user can search
alternative text.
<br />
<br />
</li>
<li><strong>Examples of Success Criterion 2.4.5 :</strong>
<ul>
<li>Dennis uses a screen reader. He wants to find all the
instances of his friend Bill in a blog post about finances. He needs
to specify case in order to avoid stopping at instances of "bill".
Later, he searches for his friend's name in a blog post about poetry
where the author never uses capital letters. In this instance he
specifies that case does not matter.</li>
<li>
Dennis he remembers a portion of a caption for something he
had seen before that he wants to find. He needs to be able to search
on the caption.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.4.5 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-nav-structure"
id="gl-nav-structure"><span class="techs-only">Implementing </span>Guideline 2.5 </a><span class="diff-renumber"> (former 2.7)</span> - Provide structural navigation.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-nav-structure">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary25"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-251">2.5.1 Discover navigation and activation keystrokes</h4><p class="sc-text">: The user can discover direct navigation and activation keystrokes both
programmatically and via perceivable labels. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.5.1 :</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.5.1 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.5.1 :</strong>
<ul>
<li>2.3.1 and 2.3.2 </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-252">2.5.2 Access Relationships: </h4><p class="sc-text">The user can access explicitly-defined relationships based on the
user's position in content (e.g. show form control's label, show label's
form control, show a cell's table headers). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.5.2 :</strong> <br />
<span class="editor-notes">@@ Editors' Note: postponed for more information about the intent of this SC. Is it
about providing flyover information? Or is it out of place and really
belongs in Principle 2? @@</span></li>
<li><strong>Examples of Success Criterion 2.5.2 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.5.2 :</strong>
<ul>
<li>also see Success Criteria 4.7.x Location in Hierarchy</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-253">2.5.3 Location in
Hierarchy:</h4><p class="sc-text"> The user can view the path of nodes leading
from the root of any content hierarchy in which the structure and
semantics are implied by presentation, as opposed to an explicit logical
structure with defined semantics (such as the HTML5 Canvas Element), or
as a consequence of decentralized-extensibility (such as the HTML5 item
/ itemprop microdata elements), and only if the user agent keeps an
internal model of the hierarchy that it does not expose via the <a class="dfn-instance"
href="#def-dom" title="definition: Document Object Model">DOM</a> or
some other accessibility mechanism. <span class="level">(Level A)</span> .</p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.5.3 :</strong> <br />
Knowing where you are in a hierarchy makes it easier to understand and
navigate information. Users who are perceiving the data linearly (such
as audio speech synthesis) do not receive visual cues of the
hierarchical information. Efficient navigation of hierarchical
information reduces keystrokes for people for whom keypress is
time-consuming, tiring, or painful. For people with some cognitive
disabilities, providing the clear hierarchy reduces cognitive effort and
provides organization.</li>
<li><strong>Examples of Success Criterion 2.5.3 :</strong>
<ul>
<li>A media player provides a hierarchical display of playlists, albums,
artists and songs, etc. When the user selects an individual item, a
breadcrumb of the categories is displayed, can be navigated and is
available programmatically.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.5.3 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-255">2.5.5 Access to Relationships which Aid Navigation:</h4><p class="sc-text"> The user can access explicitly-defined relationships based on the user's position in content, and the path of nodes leading from the root of any content hierarchy to that position. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.5.5 :</strong> <br />
Let the user use the keyboard to navigate forwards and backwards through elements that they are likely to be interested in interacting with. These elements must include, but are not limited to, enabled links and controls. This allows the user to jump between elements without having to navigate through intervening content such as blocks of text. Efficient keyboard navigation is especially important for people who cannot easily use a mouse.</li>
<li>Efficient keyboard navigation aids structured navigation by enhancing a users comprehension of their position (e.g. show form control's label, show label's form control, show a cell's table headers, etc.). </li>
<li><strong>Examples of Success Criterion 2.5.5 :</strong>
<ul>
<li>The user can press the Tab key to move the focus to the next link or control in the page, or press Shift+Tab to move in the reverse order.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.5.5 :</strong>
<ul>
<li>See 2.1.4 for discussion of letting the user configure the list of important elements to suit their task.</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-257">2.5.7 Configure Set of Important Elements:</h4><p class="sc-text"> The user has the option to
configure the set of <a href="#def-important-elements">important elements</a> for structured navigation, including
by element type (e.g. headers, list items, images). <span class="level">(Level AAA)</span> <span class="editor-notes">@@ Editor's
note: Review the definition of "important elements" @@</span></p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.5.7 :</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.5.7 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.5.7 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h3 class="guideline"><a name="gl-device-independent-handlers"
id="gl-device-independent-handlers"><span class="techs-only">Implementing </span>Guideline 2.6
</a> <span class="diff-renumber">(former 2.2)</span> - Provide access to event
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-device-independent-handlers">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary26"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-261">2.6.1
List event handlers:</h4><p class="sc-text"> The user can, through keyboard input alone, call up a list of input device <a class="dfn-instance" href="#def-event-handler"
title="definition: event handler">event handlers</a> explicitly associated with the <a class="dfn-instance" href="#def-keyboard-focus"
title="definition: keyboard focus">keyboard focus</a> element. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.6.1
:</strong> <br />
Users interacting with a web browser may be doing so by voice, keyboard, mouse or another input technology or a combination of any of these. No matter how the user is controlling the user agent, he or she need to know all the input methods assigned to a particular piece of content. </li>
<li><strong>Examples of Success Criterion 2.6.1
:</strong>
<ul>
<li>A user may tab to a link that has a flyout menu that appears OnMouseOver. The User agent needs to notify the user of this menu so he or she can know the menu is available. Other success criteria ensure the keyboard user here can interact with this menu.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.6.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-262">2.6.2
Activate any event handler:</h4><p class="sc-text"> The
user can, through keyboard input alone, <a class="dfn-instance" href="#def-activate"
title="definition: Activate">activate</a> any
input device <a class="dfn-instance" href="#def-event-handler"
title="definition: event handler">event handlers</a> explicitly
associated with the
<a class="dfn-instance" href="#def-keyboard-focus"
title="definition: keyboard focus">keyboard focus</a> element. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.6.2
:</strong> <br />
Although it should not do so, some Web content is designed to work only with certain input devices, such as a mouse, and make functionality available only through event handlers for those devices. Some users interacting with a web browser may be doing so by voice, keyboard, mouse or another input technology or a combination of any of these. No matter how the user is controlling the user agent, he or she must be able to activate any of the event handlers regardless of the interaction technology being used.</li>
<li><strong>Examples of Success Criterion 2.6.2
:</strong>
<ul>
<li>A user who cannot use a mouse needs to activate a flyout menu that normally appears OnMouseOver. The user should be able to navigate to a link and activate it using keyboard shortcuts.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.6.2
:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-263">2.6.3
Activate all event handlers:</h4><p class="sc-text"> The user can, through keyboard input alone, simultaneously <a class="dfn-instance" href="#def-activate" title="definition: Activate">activate</a> all input device <a class="dfn-instance" href="#def-event-handler" title="definition: event handler">event handlers</a> explicitly associated with the
<a class="dfn-instance" href="#def-content-focus" title="definition: content focus">content focus</a> element. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li><strong>Intent of Success Criterion 2.6.3
:</strong> <br />
One input method should not hold back another. People who don't use a mouse shouldn't necessarily have to map their input methods to the same steps a mouse user would take. </li>
<li><strong>Examples of Success Criterion 2.6.3
:</strong>
<ul>
<li>Speech input users may combine moving the mouse up, left and clicking in a single command phrase. </li>
<li>A link has an onmousedown and an onmouseup event link. The keyboard user can use 1 key click to activate both events. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.6.3
:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-store-prefs" id="gl-store-prefs">Guideline
2.7 - </a>Configure and store preference settings.</h3>
<p class="summary" id="summary27"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-271">2.7.1
Change Preference Settings</h4><p class="sc-text"> The user can change settings that impact accessibility. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-272">2.7.2
Persistent Accessibility Settings</h4><p class="sc-text">: User agent accessibility preference settings persist between sessions. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-273">2.7.3
Restore all to default:</h4><p class="sc-text"> The user can restore all preference settings to default values. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-274">2.7.4
Multiple Sets of Preference Settings:</h4><p class="sc-text"> The
user can save and retrieve multiple sets of user agent preference settings.
<span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-275">2.7.5
Restore related preferences to default:</h4><p class="sc-text"> The user can restore groups of related preference settings to default values (e.g. reset keyboard shortcuts, reset colors and sizes of rendered content). <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-276">2.7.6
Change preference setting outside the UI:</h4><p class="sc-text"> The user can adjust preference settings from outside the user agent user interface. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-277">2.7.7
Portable Preference Settings:</h4><p class="sc-text">The user can transfer preference settings across locations onto a compatible system. <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-278">2.7.8
Preferences Wizard:</h4><p class="sc-text"> A
wizard helps the user to configure the accessibility-related
user agent preferences (at least). <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.7.8
:</strong> <br />
Users who rely on accessibility settings do so for multiple reasons and may want to adjust software settings in many differing fashions. It is key to allow software settings that impact accessibility to be configured to meet these differing needs. The easier such settings are to discover, the more rapidly the user looking for such settings can tailor the software to suit his or her needs. Saving such configuration changes between browsing sessions allows the software to work the way the user wants each time the application is used.</li>
<li><strong>Examples of Success Criterion 2.7.8
</strong>
<ul>
<li>A user who relies on larger text sizes when browsing web pages, locates a text adjustment setting in a browser's menus. The user sets the text size to the size that makes web content readable. .</li>
<li>A user locates a control in a web browser called options. Activating this control leads to a series of tabs for adjusting multiple browser settings. One tab is listed as accessibility and has settings such as text size, use custom style sheet, display alternative text in place of images, enable caret browsing and other settings determined to be of benefit to users with disabilities.</li>
<li> A user is exploring settings for a web browser and locates an option called accessibility. The user is then guided through a series of questions asking about how he or she prefers to use software. Questions such as color preference, text size, ability to view images, the need for captions on videos and such are asked. When the user completes these questions, appropriate browser options are configured and stored.</li>
<li>A user who has configured accessibility settings in a browser needs to use that application in the same browser on another computer. The browser allows the user to transfer such settings from one computer to another, saving the need to reconfigure the second machine.</li>
<li class="editor-notes">@@ Editors' Note: add another example of persistence@@</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.7.8
</strong>
<ul>
<li>SCORM <span class="editor-notes">Editors' Note: (Jutta's work) - find current reference @@</span></li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-configure-controls"
id="gl-configure-controls"><span class="techs-only">Implementing </span>Guideline 2.8 - </a> Provide toolbar
configuration.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-configure-controls">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary28"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-281">2.8.1 Configure Position:</h4>
<p class="sc-text"> When graphical <a class="dfn-instance" href="#def-ua-ui"
title="definition: user agent user interface">user agent user interfaces</a> have toolbars, panels, inspectors, or similar, the user can add, remove and configure the position of <a class="dfn-instance" href="#def-ui-control"
title="definition: user interface control">user agent user interface
controls</a> from a pre-defined set. <span class="level">(Level AAA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.8.1 :</strong> <br />
The objective of this criteria is to allow the user to customize the toolbars of a user agent in ways that work best for the method in which he or she is using the browser. This can reduce keystrokes, bring buttons into view that are hidden by default or otherwise allow the user to interact with the user agent in a more efficient fashion. Users with dexterity impairments or mobility impairments may have problems making the large movements required to select between non-adjacent controls which they need to use frequently. Similarly users with low vision may have to excessively move their magnified view-port to see frequently used controls. Enabling these controls to be situated together removes much of the strain faced by these users, and increases productivity as task completion times are decreased. </li>
<li><strong>Examples of Success Criterion 2.8.1 :</strong>
<ul>
<li>Martin accesses the computer by pressing keys with a stick held in his mouth known as a mouthstick and gets around the user agent with taps on the tab and arrow keys. The designers of a user agent have decided to place a button for printing a web page as the last button on a toolbar. This button requires six presses of a right arrow key to reach for Carl and is the only button he uses on the toolbar. Using a preferences dialog, Martin is able to configure this toolbar to only show the Print button, reducing the number of presses he must issue with his mouthstick to one. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.8.1 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-282">2.8.2 Restore Default Toolbars: </h4><p class="sc-text">The
user can restore the default toolbar, panel, or inspector configuration. <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.8.2 :</strong> <br />
Mistakes happen. If a user has modified the toolbar incorrectly it can often be difficult to return to a stable state so that these errors can be corrected. There are additional pressures in this regard for people with learning difficulties who make more use of toolbars than they do of textual menus. Building an easily selectable mechanism to restore these defaults saves user time and reduces stress. </li>
<li><strong>Examples of Success Criterion 2.8.2 :</strong>
<ul>
<li>Jack is an 80 year old web surfer who is intellectually very sharp but experiences tremors in his hands when required to make fine movements with the mouse. To help himself he is setting up the toolbar so that 'spacers' are placed between each component to prevent accidental selection of adjacent buttons. Today his tremors are particularly bad and Jack makes a number of mistakes becoming increasingly frustrated that while trying to correct these errors he begins to make many more. Jack just wants to start over. Luckily the browser manufacturer has included an easy mechanism to restore the default toolbar configuration. Jack chooses this option and successfully starts over the next day. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.8.2 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-time-independent"
id="gl-time-independent"><span class="techs-only">Implementing </span>Guideline 2.9</a><span class="diff-renumber"> (former 2.3)</span> - Allow time-independent
interaction.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-time-independent">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary29"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-291">2.9.1
Timing Adjustable</h4><p class="sc-text">:
Where time limits for user input are <a href="#def-recognize">recognized</a>
and controllable by the user agent, the user can extend the time
limit. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.9.1
:</strong> <br />
Users of assistive technology, such as screen readers, and those who may require more time to read or understand and act upon content (e.g. individuals with reading disabilities or non-native readers of the presented language) should be able to extend or override any content/author imposed presentation / interaction time limits.</li>
<li><strong>Examples of Success Criterion 2.9.1
:</strong>
<ul>
<li>News Alerts: A news organizations Web site has a region of the home page which presents featured stories, cycled every 3 seconds. A user with low vision, using a screen magnifier, requires more than three seconds to read the news item and select it. The user agent provides the user with a global option to freeze all timed events using a keyboard command. Another keyboard command resumes the timed presentation. </li>
<li>Session Inactivity Timeouts: A screen reader user is logged into a financial services Web site and is reading the site's detailed privacy policy. Because of security policy, the site will terminate the session of any user who has been inactive for 5 minutes. A prompt will appear warning of the impending log off without further action. This user is able to select an option in her non-visual user agent that automatically responds to those prompts if the user agent is currently reading the content.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.9.1
:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<h4 class="sc-title" id="sc-292">2.9.2 Retrieval Progress:</h4>
<p class="sc-text">
The user agent shows the progress of content retrieval. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.9.2 :</strong> <br />
Users need to know that their actions are producing results even if
there is a time delay. Users who cannot see visual indications need to
have feedback indicating a time delay and have an idea of where they are
in the retrieval process. This reduces errors and unnecessary duplicate
actions.</li>
<li><strong>Examples of Success Criterion 2.9.2 :</strong>
<ul>
<li>The user has clicked on a link that is downloading a large file. The
user agent displays a programmatically available progress bar. If the
progress stops, the user agent displays a message that it has timed out.</li>
<li>The user has entered data in a form and is waiting for a response from
the server. If the response hasn't been received in 5 seconds, the user
agent displays a programmatically available message that it is waiting
for a response. If the process times out, the user agent displays a
message that it has timed out.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.9.2 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h3 class="guideline"><a name="gl-prevent-flash"
id="gl-prevent-flash"></a><span class="techs-only">Implementing </span>Guideline 2.10<span class="diff-renumber"> (former 2.4)</span> - Help users avoid flashing that could cause seizures.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-prevent-flash">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary210"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-2101">2.10.1
Three Flashes or Below Threshold:</h4><p class="sc-text"> In its default configuration, the user agent does not display any user interface components or recognized content that flashes more than three times in any one-second period, unless the flash is below the general flash and red flash thresholds. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.10.1
:</strong> <br />
The intent of this Success Criterion is to guard against inducing seizures due to photosensitivity, which can occur when there is a rapid series of general flashing, or red flash. A potentially harmful flash occurs when there is a pair of significantly opposing changes in luminance, or irrespective of luminance, a transition to or from a saturated red occurs.</li>
<li><strong>Examples of Success Criterion 2.10.1
:</strong>
<ul>
<li>A single, double, or triple flash -- as long as it does not include changes to or from a saturated red -- may be used to attract a user's attention, or as part of an interface animation. </li>
<li>An error condition is indicated by flashing that continues until acknowledged by the user. In order to avoid triggering seizures, the flashing is limited to fewer than three times per second, and, to be extra cautious, it is not red.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.10.1
:</strong>
<ul>
<li> <a href="http://stakeholders.ofcom.org.uk/binaries/broadcast/guidance/gn_flash.pdf">ITC Guidance Note for Licensees on Flashing Images and Regular Patterns in Television</a>: http://stakeholders.ofcom.org.uk/binaries/broadcast/guidance/gn_flash.pdf </li>
</ul>
</li>
</ul>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-2102">2.10.2
Three Flashes:</h4><p class="sc-text"> In its default configuration, the user agent does not display any user interface components or recognized content that flashes more than three times in any one-second period (regardless of whether not the flash is below the general flash and red flash thresholds). <span class="level">(Level AAA)</span> [<a
href="http://www.w3.org/TR/WCAG20/#glossary">WCAG 2.0</a>]</p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.10.2
:</strong> </li>
<li>The intent of this Success Criterion is to guard against inducing seizures due to photosensitivity, which can occur when there is a rapid series of general flashing, or red flash. A potentially harmful flash occurs when there is a pair of significantly opposing changes in luminance, or irrespective of luminance, a transition to or from a saturated red occurs. 2.10.2 has the same effect as 2.10.1, only goes further to ensure that more sensitive users can traverse the Web without potentially harmful effects. </li>
<li><strong>Examples of Success Criterion 2.10.2
:</strong>
<ul>
<li>refer to 2.10.1</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.10.2
:</strong>
<ul>
<li>refer to 2.11.2 and 2.11.6</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-control-inaccessible-content"
id="gl-control-inaccessible-content"><span class="techs-only">Implementing </span>Guideline 2.11 - </a> Provide control of
content that may reduce accessibility. <span class="diff-renumber">(former 2.9)</span>
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-control-inaccessible-content">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary211"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-2111">2.11.1 Background Image
Toggle:</h4><p class="sc-text"> The user has the global option to hide/show <a href="#def-background-images">background images</a>. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.1 :</strong> <br />
Users can have difficulty reading text or recognizing images that are shown against variable backgrounds. Background images can also be distracting, especially to some people with cognitive impairments. </li>
<li><strong>Examples of Success Criterion 2.11.1 :</strong>
<ul>
<li>John finds multiple images behind the text he is reading distracting. He navigates to his favorite news site where he finds today's weather displayed over a picture of a sunny sky with fluffy clouds. He activates a button on a toolbar named "Hide Background" and now can easily determine he's in for a day filled with sunshine. </li>
<li>Sasha requires high contrast to be able to discriminate the shape of letters. She always sets a preference in her browser to turn off background images, so that she can see the text clearly without the variations in the background. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.1 :</strong>
<ul>
<li>1.1.1 Configure Default Rendering allows the user to hide foreground images by replacing them with alternative content, but 2.11.1 extends this to background images in languages such as HTML that do not support alternative content for background images. </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2112">2.11.2 Time-Based Media
Load-Only:</h4>
<p class="sc-text"> The user can
load time-based media content <span class="editor-notes">@@ Editors' Note: DEFINE@@</span>
such that a placeholder is displayed, but the content is not
played until <a class="dfn-instance" href="#def-user-request"
title="definition: Explicit user request">explicit user request</a>. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.2 :</strong> <br />
</li>
<li><strong>Examples of Success Criterion 2.11.2:</strong>
<ul>
<li>Jill browses browses the web using a screen reader to listen to the text of web pages. She navigates to her favorite shopping site and is greeted with trumpets blaring and an announcer shouting "Sale, sale, sale!" The audio is so loud that she can no longer hear the web page content. Jill closes her browser and changes a setting titled Play Audio on Request to yes and visits her shopping site again. This time she can read the content and when she is ready plays the audio and smiles, thinking of the deal's she is about to find. </li>
<li>Jamie has epilepsy that's triggered by certain types of audio. She sets browser so that content does not play automatically so she can avoid audio that could trigger her epilepsy. </li>
<li>Kendra has photo-epilepsy. She sets her browser so that content does not play automatically so she can avoid flashing content that could trigger her photo epilepsy. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.2:</strong>
<ul>
<li>Guideline 2.10 Help users avoid flashing that could cause seizures.</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2113">2.11.3 Execution
Placeholder:</h4><p class="sc-text"> The user can
render a <a href="#def-placeholder">placeholder</a> instead of executable
content that would normally be contained within an on-screen area (e.g.
Applet, Flash), until <a class="dfn-instance" href="#def-user-request"
title="definition: Explicit user request">explicit user request</a> to
execute. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-2114">2.11.4 Execution Toggle:</h4><p class="sc-text"> The
user can turn on/off the execution
of executable content that would not normally be contained within a
particular area (e.g. Javascript). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<h4 class="sc-title" id="sc-2115">2.11.5 Playback Rate Adjustment for Prerecorded Content:</h4>
<p class="sc-text"> The user can adjust the playback rate of prerecorded time-based media content, such that all of the following are true: <span class="level">(Level A)</span> </p>
<ul>
<li>The user can adjust the playback rate of the <span class="sc-txt">time-based media</span> tracks to between 50% and 250% of real time. </li>
<li>Speech whose playback rate has been adjusted by the user maintains pitch in order to limit degradation of the speech quality.</li>
<li>Audio and video tracks remain synchronized across this required range of playback rates.</li>
<li>The user agent provides a function that resets the playback rate to normal (100%).</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.5:</strong> <br />
Users with sensory and cognitive impairments may have difficulty following or understanding spoken audio when presented at the normal playback rate. By slowing down the audio presentation of speech, while maintaining the pitch, or frequency characteristics, users are better able to follow the spoken content. For users with visual impairments familiar with the speeding up of speech presentation using screen readers or digital audio book players, the ability to speed up the audio, while maintaining pitch, allows those users to skim spoken audio without loss of understandability of the speech. Users with learning disabilities may be distracted or otherwise unable to follow complex animations or instructional video. By allowing the presentation to be slowed, the user has a better opportunity to observe the visual events of the animation. Additionally, a person may want to slow down the media if they are trying to take notes, and do so slowly because of language or dexterity impairments, etc. </li>
<li><strong>Examples of Success Criterion 2.11.5:</strong>
<ul>
<li>Timo experienced a traumatic brain injury and has difficulty in comprehending speech. When listening to episodes of his favorite podcast on the Web, he slows down the audio by 50% and is able to understand the interviewer's and guest's question and answer session. </li>
<li>Anu is a blind university student who has grown up with digital talking book players, and regularly listens to spoken audio at 200% of normal speaking rate. In studying for exams, she reviews the online lecture videos from her History course, adjusting the presentation rate to 2x on the Web video player, in order to quickly review the material, and slowing the presentation down to normal rate when she encounters material she needs to review carefully. </li>
<li>Perttu has a learning disability and requires a longer time to follow instructions. He likes to cook and is watching a cooking demonstration on the Web. The instructions go by too quickly, and Perttu slows the video player to half speed in order to make it easier to follow the recipe being prepared. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.5:</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2116">2.11.6 Stop/Pause/Resume
Time-Based Media:</h4><p class="sc-text"> The user can stop, pause, and resume rendered audio and
<a class="dfn-instance" href="#def-animation"
title="definition: Animation">animation</a> content (including video and
animated images) that last three or more seconds at their default playback
rate. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.6:</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.11.6:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.6:</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2117">2.11.7 Navigate Time-Based Media:</h4><p class="sc-text"> The user can navigate along the timebase using a continuous scale, and by relative time units within rendered audio and animations (including video and animated images) that last three or more seconds at their default playback rate. <span class="level">(Level A)</span>
</p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.7 :</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.11.7 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.7 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2118">2.11.8 Semantic Navigation of Time-Based Media:</h4><p class="sc-text"> The user can navigate by semantic structure within the time-based media, such as by chapters or scenes present in the media <span class="level">(Level AA)</span>.</p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.8 :</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.11.8 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.8 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-2119">2.11.9 Track Enable/Disable of Time-Based Media:</h4><p class="sc-text"> During time-based media playback, the user can determine which tracks are available and select or deselect tracks. These selections may override global default settings for captions, audio descriptions, etc. <span class="level">(Level AA)</span></p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.9 :</strong> <br />
Not yet drafted</li>
<li><strong>Examples of Success Criterion 2.11.9 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.9 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-21110">2.11.10 Sizing Playback Viewport: </h4>
<p class="sc-text"> The user can adjust the size of the time-based media up to the full height or width of the containing viewport. In doing so, the user can preserve aspect ratio and adjust the size of the playback viewport to avoid cropping, within the scaling limitations imposed by the media itself. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.10 :</strong> <br />
User needs video larger but still needs access to other application (take notes during playback), fullscreen does not allow that. Content should reflow as user adjusts playback viewport.</li>
<li><strong>Examples of Success Criterion 2.11.10 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.10 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-21111">2.11.11 Scale and position alternative media tracks:</h4>
<p class="sc-text"> The user can scale and position alternative media tracks independent of base video. <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.11 :</strong> <br />
Text scaling - default setting should apply, UA should allow separate
control of the caption tracks. User needs larger captions. Snap captions outside of video, change text size and caption viewport size/position. User need to reposition and make the sign language track larger.</li>
<li><strong>Examples of Success Criterion 2.11.11 :</strong>
<ul>
<li>To be written <span class="editor-notes">@@ Editors' Note: University of Toronto had working examples 10 years ago. Geoff Freed and Larry Goldberg session at CSUN 2 years ago showed many examples caption in different locations, but not the user could disconnect and move where needed.@@</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.11 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-21112">2.11.12 Adjust Playback Contrast and Brightness: </h4><p class="sc-text"> User can control the contrast and brightness of the content within the playback viewport. </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 2.11.12 :</strong> <br />
Text scaling - default setting should apply, UA should allow separate
control of the caption tracks. User needs larger captions. Snap captions outside of video, change text size and caption viewport size/position. User need to reposition and make the sign language track larger.</li>
<li><strong>Examples of Success Criterion 2.11.12 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 2.11.12 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
<div class="applic-notes">
<h4 id="app-note-control-video">Applicability Notes:</h4>
<p>The guideline only applies to images, animations, video, audio, etc. that
the user agent can <a href="#def-recognize">recognize</a>. </p>
<p> </p>
<p class="editor-notes">@@ Editors' Note: If the browser is playing the video natively, there is only 1 user agent. In that case, it falls on the browser to meet the UAAG spec. @@</p>
<p> </p>
<p class="editor-notes">@@ Editors' Note: If an author uses windows media player inside the video element, the browser needs to map its native controls to the embedded wmp controls, and provide access to all the controls. @@</p>
<p> </p>
<p class="editor-notes">@@ Editors' Note: The user needs to be able to define rendering parameters of playback at render-time. @@</p>
</div>
<h2 class="principle"><a name="principle-understandable"
id="principle-understandable"></a>Principle 3: Ensure that the user interface is
understandable</h2>
<h3 class="guideline"><a name="gl-avoid-unnecessary-messages"
id="gl-avoid-unnecessary-messages"></a><span class="techs-only">Implementing </span>Guideline 3.1 - Help users avoid
unnecessary messages.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/#gl-avoid-unnecessary-messages">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary31"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<p class="editor-notes">@@ Editors' Note: Add SC based on this note from IRC of 10 November 2010: We could consider adding to this section a recommendation that messages have a checkbox that lets the user avoid getting the message again. But I'm not sure how we could write it to have an appropriate scope, that is only apply to messages where it's appropriate. AND when you do have those check boxes, it's also useful to have something in the application's settings that allows the user to reset those to their default, thus making all the messages visible again.@@</p>
<h4 class="sc-title" id="sc-312">3.1.2 Option to Ignore:</h4>
<p class="sc-text"> The
user can turn off rendering of
non-essential or low priority text messages or updating/changing information in the content based on priority properties
defined by the <a href="#def-author">author</a> or the user agent. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.1.2 :</strong> <br />
Messages designed to inform the user can be a burden to users for whom
keypress is time-consuming, tiring, or painful. It's important that
these users be able to avoid unnecessary messages.</li>
<li><strong>Examples of Success Criterion 3.1.2 :</strong>
<ul>
<li>The browser has an update ready. The user should have the option to be
informed of an update or, instead, only get update information when the
user actively requests it.</li>
<li>A web page has a stock market ticker display. A user with cognitive disabilities is distracted by the page flicker and wishes to turn off the update. The browser has an menu option to set the level of interruptions, that the user sets to off. <span class="editor-notes">@@ Editors' Note: add this example @@</span></li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.1.2 :</strong>
<ul>
<li class="sc-txt"><a href="http://www.w3.org/WAI/intro/aria">WAI-ARIA</a> </li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-avoid-mistakes"
id="gl-avoid-mistakes"><span class="techs-only">Implementing </span>Guideline 3.2 - </a> Help users avoid and correct
mistakes.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-avoid-mistakes">Return to Guideline</a>]</span></h3>
<blockquote>
<p class="summary" id="summary32"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
</blockquote>
<div class="sc-level">
<h4 class="sc-title" id="sc-321">3.2.1 Form Submission:</h4><p class="sc-text"> The user can specify whether or not recognized form submissions must be confirmed. <span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.2.1 :</strong> <br />
Users need to be protected against accidentally submitting a form. Some
assistive technologies use the Enter key to advance to the next field.
If the form is designed to submit on Enter, the user can unknowingly
submit the form. Those users need to be able to disable the ability to
submit on Enter. </li>
<li><strong>Examples of Success Criterion 3.2.1 :</strong>
<ul>
<li>Upon installation of a web browser, a screenreader user selects an
option to disable form submission on Enter. This is a preference option
that can be easily discovered and changed by the user in the future.
This allows the user to complete forms from the banking website knowing
that the submit button must be selected in order to submit the form.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.2.1 :</strong>
<ul>
<li class="editor-notes">@@ Editors' Note: link to section 2.1, especially 2.1.2 and 2.1.10 @@</li>
</ul>
</li>
</ul>
</div>
<h3 class="guideline"><a name="gl-doc-access-features"
id="gl-doc-access-features"><span class="techs-only">Implementing </span>Guideline 3.3 - </a> Document the user agent user
interface including all accessibility features.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-doc-access-features">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary33"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<div class="sc-level">
<h4 class="sc-title" id="sc-331">3.3.1 Accessible documentation:</h4>
<p class="sc-text"> The product <a class="termdef" href="#def-documentation" title="definition: documentation">documentation</a> is available in a format that meets success criteria of WCAG 2.0 Level "A" or greater. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.3.1 :</strong> <br />
User agents will provide documentation in a format that is accessible.
If provided as Web content, it must conform to WCAG 2.0 Level "A" and
if not provided as Web content, it must be in conformance to a
published accessibility benchmark and identified in any conformance
claim for the user agent. This benefits all users who utilize
assistive technology or accessible formats.</li>
<li><strong>Examples of Success Criterion 3.3.1 :</strong>
<ul>
<li>A user agent installs user documentation in HTML format conforming to
WCAG 2.0 Level "A". This documentation is viewed within the user agent
and is accessible in accordance with the conformance of the user agent
to UAAG 2.0.</li>
<li>A user agent provides documentation in HTML format conforming to WCAG
2.0 Level "AA" and is available online. In addition, the user agent
provides user documentation in a locally installed digital talking
book content format in conformance with a recognized, published
format. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.3.1 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-332">3.3.2 Document Accessibility
Features: </h4><p class="sc-text"> All user agent features
that benefit accessibility are documented. <span class="level">(Level A)</span> <span class="editor-notes"> @@ Editors' Note: write a definition of "benefit accessibility" - as contributing to conforming to these guidelines or a feature specifically added to improve accessibility @@</span></p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.3.2 :</strong> <br />
User agent documentation that includes listings and descriptions of
features supporting or benefiting accessibility permits users to have
access to a description of accessibility and compatibility features.
This benefits all users with disabilities who may require assistance
in identifying which accessibility features may be present or how to
configure those features to work with assistive technology.<br />
<br />
The user should be able to easily discover detailed information about the user agent’s adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, platform standards such as MSAA or JAA, and third-party standards such as ISO 9241-171, and should be able to do so without installing and testing the accessibility features.</li>
<li><strong>Examples of Success Criterion 3.3.2 :</strong>
<ul>
<li>In a section entitled "Browser Features Supporting Accessibility", a
vendor provides a detailed description of user agent features which
provide accessibility, describing how they function, and listing any
supported third party assistive technologies that may be supported or
required.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.3.2 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-333">3.3.3 Changes Between
Versions: </h4><p class="sc-text"> Changes to features that benefit accessibility since the previous user agent release are documented. <span class="editor-notes">@@Editors' Note: Link to the definition to benefit accessibility from previous 3.3.2 @@</span><span class="level">(Level AA)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.3.3 :</strong> <br />
As accessibility features are implemented in new versions it is important for users to be able to be informed about these new features and how to operate them. The user should not have to discover which new features were implemented in the new version.</li>
<li><strong>Examples of Success Criterion 3.3.3 :</strong>
<ul><li>
Sample text: "In this version, we added the ability to display tooltips on elements with a title attribute when using the keyboard. With caret browsing turned on simply arrowing onto an element with a title the tooltip will remain visible while the caret is within the element."</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.3.3 :</strong>
<ul>
<li>N/A</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-334">3.3.4 Centralized View: </h4> <p class="sc-text">There is a dedicated section of the documentation that presents a view of all features of the user agent necessary to meet the requirements of User Agent Accessibility Guidelines 2.0. <span class="level">(Level AAA)</span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.3.4 :</strong> <br />
Specific accessibility features are important for users to know about and how to operate. The user should not have to discover where the accessibility features are documented in context (although that too is very useful). A specific section devoted to only accessibility features (e.g. keyboard shortcuts, how to zoom the viewport, where to find accessibility configuration settings), would make it easier for user to become more functional more quickly with the user agent.</li>
<li><strong>Examples of Success Criterion 3.3.4 :</strong>
<ul>
<li>A specific section in the documentation (local or online) detailing accessibility features of the user agent.<span class="editor-notes">[@@ Editor's Note: what about accessibility features of plugins, extensions, etc. they are not user agents by them selves. how do user find out about accessibility features if any in the extension?@@</span>]</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.3.4 :</strong>
<ul>
<li>N/A</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-335">3.3.5 Context Sensitive
Help: </h4><p class="sc-text"> There is context-sensitive
help on all user agent features that benefit accessibility. <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.3.5 :</strong> <br />
The purpose of this criteria is to help maximize the discovery of user agent features that benefit accessibility.</li>
<li><strong>Examples of Success Criterion 3.3.5 :</strong>
<ul>
<li>A user is exploring the menus of a user agent and finds a feature named Use My Style Sheet. Activating help the user quickly learns that this feature allows custom CSS stylesheets to be created to help make web content more accessible.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.3.5 :</strong>
<ul>
<li>N/A</li>
</ul>
</li>
</ul>
</div>
<div class="sc-level">
<h3 class="guideline"><a name="gl-predictable-operation" id="gl-predictable-operation"></a><span class="techs-only">Implementing </span>Guideline 3.4 - The user agent must behave in a predictable fashion.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-predictable-operation">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary34"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-341">3.4.1 Avoid unpredictable focus <span class="diff-renumber">[formerly 3.4.2, before that 5.4.2, and 1.9.10, broadened] </span>:</h4><p class="sc-text"> The user can prevent focus changes that are not a result of explicit user request. <span class="level">(Level A)</span></p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.4.1 :</strong> <br />
Users need to know that navigation in a web page is going to start in a predictable location and move in a predictable fashion. If a page moves the initial focus to somewhere other than the beginning of the page, the user may not realize they have skipped over some content, especially if they can only see a small portion of the page at a time. Similar problems may occur if the content or user agent automatically moves the focus while the user is reading or entering data on a page. If the focus moves without the user recognizing it, they can easily end up entering data in an incorrect field or taking other unintentional actions. Users can also become confused or disoriented when a window scrolls when they haven't requested it. This is particularly problematic for users who can only see a small portion of the document, and thus have to use more effort to determine their new context. Such users also are more likely to continue typing, not immediately realizing that the context has changed. Users for whom navigation is time consuming, tiring, or painful (including those using screen readers or with impaired dexterity) may also need more steps to return to the area where they want to work. While we recognize it may improve accessibility for some users on some pages to have the page to set focus to specific link or field when the page loads, it can also be detrimental for some users, and therefore users needs to be in control of this behavior. </li>
<li><strong>Examples of Success Criterion 3.4.1 :</strong>
<ul>
<li>Jerome has loaded a page that sets its default focus to a search box. Because he wants to read the content of the page, rather than starting by entering data, it takes him additional scrolling to get to the content that was not in the search box. To prevent this, he adjusts his browser's settings to disable the automatic focus change on this page. </li>
<li>Jessica uses a screen enlarger, and loads a page that contains instructions followed by a form. If the page automatically moves the keyboard focus to the form, she may not realize there were instructions. To avoid this problem, she sets an option to prevent default focus changes. </li>
<li>James uses speech recognition. He speaks his credit card number by saying several digits and, if needed, Tab keys, in a single phrase. He needs to know ahead of time whether it is necessary to include the Tab command in the phrase. </li>
<li>Joey is filling in a Web form that asks for his phone number using three separate fields. When she types the three digits of her area code into the first field, the browser automatically moves the focus to the second field. This can be a problem for two reasons, first because if Joey is not looking at the screen she does not realize that the focus has moved for her, and so she presses the Tab key to move it manually, not realizing that this now puts the focus on the third field rather than the the second. It can also pose a problem if Joey realizes that she typed one digit incorrectly in the area code field, because when she presses Shift+Tab to return and edit that field, the browser or content script checks the number of digits that have been entered, and seeing that it is three, automatically moves the focus once again, preventing her from editing the number. To avoid these problems, Joey goes to her browser's Preferences dialog box and checks the option that prevents focus changes that she has not explicitly requested. </li>
<li>Justine uses a keyboard macro to execute a multistep command at a specific location. The focus changes without her control, so the command fails or executes with unpredictable results. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.4.1 :</strong>
<ul>
<li>UAAG 2.0 3.10.8 Don't Move Focus</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-342">3.4.2 Avoid Side Effects of Navigation<span class="diff-renumber"> [former 1.9.1, before that 3.11.11, changed]</span>:</h4><p class="sc-text"> The user can move the keyboard focus without causing the user agent to take any further action, other than the presentation of information (e.g. scrolling or pop-ups that do not change the focus or selection). <span class="level">(Level A)</span></p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 3.4.2 :</strong> <br />
People do not expect side effects when moving the keyboard focus. If users fail to notice side effects, they could end up doing something disastrous, and this is especially likely for users of assistive technology who cannot see changes happening elsewhere on the screen. Users may also find it confusing or disorienting if the effect causes unexpected focus movement or changes in context. If the user agent does implement side effects to keyboard navigation, it is recommended that it provide a user preference setting to disable them. However, in some cases it may be more appropriate to provide a separate navigation mechanism that avoids side effects, such as allowing the user to hold down the Ctrl key while navigating to avoid changing selection or choice. <br /><br />
Note: It may not be possible for the user agent to detect or prevent side effects implemented by scripts in the content, but the user agent is required to prevent side effects that are under its control. </li>
<li><strong>Examples of Success Criterion 3.4.2 :</strong>
<ul>
<li>Murray uses a screen enlarger that allows him to see the element with the focus and a small area around it. He explores a dialog box by repeatedly pressing the Tab key to move to, and read, each control in succession, although he has to use the arrow keys to navigate between options in an option group. On this platform moving the focus to an option control automatically chooses that option, making it cumbersome for him because of the need to reset the choice to its original state afterward. Fortunately, the platform also has a convention that holding down the Ctrl key while navigating will move the focus without changing selection or option choice, so Murray uses this while exploring. His Web browser implements its own form controls and navigation mechanisms rather than using the platform's infrastructure, but it also implements this Ctrl-key mechanism for users like Murray.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 3.4.2 :</strong>
<ul>
<li><a href="#gl-viewport-orient">UAAG 2.0 1.8.7 Don't Move Focus</a></li>
</ul>
</li>
</ul>
<p class="editor-notes">@@ Editors' Note: Missing: Greater ease in interpreting security messaging. Should be cross-referenced with the security working group. @@</p>
</div>
<h2 class="principle"><a name="principle-AT-access"
id="principle-AT-access"></a>PRINCIPLE 4: Facilitate programmatic access</h2>
<h3 class="guideline"><a name="gl-AT-access" id="gl-AT-access"></a><span class="techs-only">Implementing </span>Guideline 4.1 - <span class="principle">Facilitate
programmatic access to assistive technology </span>
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-AT-access">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary41"><strong>Summary</strong>: Be compatible with assistive technologies by supporting platform standards (4.1.1), including providing information about all menus, buttons, dialogs, etc. (4.1.2, 4.1.6), access to DOMs (4.1.4), and access to structural relationships and meanings, such as what text or image labels a control or serves as a heading (4.1.5). Where something can't be made accessible, provide an accessible alternative version, such as a standard window in place of a customized window (4.1.3). Make sure that that programmatic exchanges are quick and responsive (4.1.7).</p>
<h4 class="sc-title" id="sc-411">4.1.1 Platform Accessibility Architecture:</h4>
<p class="sc-text"> The user agent supports a <a class="termdef"
href="#def-access-platform-arch">platform accessibility architecture</a>
relevant to the <a class="termdef" href="#def-operating-environment" title="definition: operating environment">operating environment</a>. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.1 :</strong> <br />
Computers, including many smart phones, have accessibility features and support for Assistive Technologies built into the operating system. Assistive technologies often use a combination of methods to get information about, and manipulate, a user agent's user interface and the content it's rendering. These methods include <a class="dfn-instance"
href="#def-dom" title="definition: Document Object Model">DOM</a>s, accessibility APIs such as MSAA or JAA, general-purpose platform APIs such as those used to determine a window's title, application-specific APIs that that are typically a last resort when an application does not make all information available through the former means, and hard-coded heuristics. It is the user agent's responsibility to make the necessary information and facilities available through the appropriate corresponding means. Platform accessibility API is particularly important because it provides common functionality across all (or at least all well behaved) applications running on the platform, reducing the amount of special-casing the assistive technology has to implement for each of the hundreds of applications it supports.<br />
</li>
<li><strong>Examples of Success Criterion 4.1.1 :</strong>
<ul>
<li>Browser A is developing a new user interface button bar for their Microsoft Windows product. The developer codes a call to the MSAA API for the functionality.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.1 :</strong>
<ul>
<li>Microsoft's Active Accessibility (MSAA)<a href="http://msdn.microsoft.com/en-us/library/ms971310.aspx"> http://msdn.microsoft.com/en-us/library/ms971310.aspx</a></li>
<li>User Interface (UI) Automation <a href="http://msdn.microsoft.com/en-us/library/ms747327.aspx">http://msdn.microsoft.com/en-us/library/ms747327.aspx</a></li>
<li>Gnome Accessibility Toolkit (ATK) <a href="http://library.gnome.org/devel/atk/">http://library.gnome.org/devel/atk/</a></li>
<li>KDE Assistive Technology Service Provider Interface (AT-SPI) <a href="http://accessibility.kde.org/developer/atk.php">http://accessibility.kde.org/developer/atk.php</a></li>
<li>Mac Accessibility API <a href="http://developer.apple.com/ue/accessibility/">http://developer.apple.com/ue/accessibility/</a></li>
<li>Iaccessible2 <a href="http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2">http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2</a>, <a href="http://www-03.ibm.com/able/open_computing/open_source_windows.html">http://www-03.ibm.com/able/open_computing/open_source_windows.html</a></li>
<li>Accessibility API Cross reference <a href="http://www.mozilla.org/access/platform-apis">http://www.mozilla.org/access/platform-apis</a></li>
<li>PDF Accessibility API Reference <a href="http://www.adobe.com/devnet/acrobat/pdfs/access.pdf">http://www.adobe.com/devnet/acrobat/pdfs/access.pdf</a></li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-412">4.1.2 Name, Role, State, Value,
Description: </h4>
<p class="sc-text">For all user interface components including user interface, rendered content, generated content, and alternative content, the user agent makes available the name, role, state, value,
and description via a <a class="termdef"
href="#def-access-platform-arch">platform accessibility architecture</a>. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.2 :</strong> <br />
The information that assistive technology requires is the
<ul><li>Name (component name)</li>
<li>Role (purpose, such as alert, button, checkbox, etc)</li>
<li>State (current status, such as busy, disabled, hidden, etc)</li>
<li>Value (information associated with the component such as, the data in a text box, the position number of a slider, the date in a calendar widget)</li>
<li>Description (user instructions about the component). </li>
</ul>
For every component developed for the user agent, pass this information to the appropriate accessibility platform architecture or application program interface (API). Embedded user agents, like media players can pass Name, Role, State, Value and Description via the WAI-ARIA techniques. <br />
</li>
<li><strong>Examples of Success Criterion 4.1.2 :</strong>
<ul>
<li>A browser is developing a component to search a listing of files stored in folders. The text box to enter the search terms is coded to pass the following information:Name=<br />
State<br />
STATE_FOCUSABLE<br />
STATE_SELECTABLE<br />
<span class="editor-notes">@@ Editors' Note: This needs to be finished and be a legitimate example. Help! @@</span> </li>
<li>A media player implements a slider to control the sound volume. The developer codes the component to pass the following information to the accessibility API:<br />
Name = Volume control<br />
Role = Slider<br />
States & Values<br />
aria-valuenow<br />
The slider’s current value.<br />
aria-value-min<br />
The minimum of the value range<br />
aria-value-max<br />
The maximum of the value range <br />
Description<br />
aria-describedby = 'Use the right or left arrow key to change the sound volume.' <br />
</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.2 :</strong>
<ul>
<li><span class="editor-notes">@@ Editors' Note: [more needed]</span><br />
http://msdn.microsoft.com/en-us/library/ms697187</li>
<li>http://www.mozilla.org/access/windows/msaa-server</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-413">4.1.3 Accessible
Alternative:</h4>
<p class="sc-text"> If a component of the user agent user interface cannot be exposed through the platform accessibility architecture, then the user agent provides an equivalent alternative that is exposed through the platform accessibility architecture. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.3 :</strong> <br />
Users who rely on assistive technology need to be able to carry out all tasks provided by the user agent, just like everyone else. When a particular user interface component cannot support for the platform accessibility architecture, and thus can't be made compatible with assistive technology, the user agent should let the user achieve the same goal using another component that IS fully accessible.</li>
<li><strong>Examples of Success Criterion 4.1.3 </strong>:
<ul>
<li>The user agent provides a single, complex control for 3-dimensional manipulation of a virtual object. This custom control cannot be represented in the platform accessibility architecture, so the user agent provides the user the option to achieve the same functionality through an alternate user interface, such as a panel with several basic controls that adjust the yar, spin, and roll independently. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.3 </strong>:
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-414">4.1.4 Programmatic Availability of
DOMs:</h4><p class="sc-text"> If the user agent implements one or more <a class="dfn-instance"
href="#def-dom" title="definition: Document Object Model">DOMs</a>, they must be
made programmatically available to assistive technologies. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.4 :</strong> <br />
User agents (and other applications) and assistive technologies use a combination of DOMs, accessibility APIs, native platform APIs, and hard-coded heuristics to provide an accessible user interface and accessible content (<a href="http://accessibility.linuxfoundation.org/a11yspecs/atspi/adoc/a11y-dom-apis.html">http://accessibility.linuxfoundation.org/a11yspecs/atspi/adoc/a11y-dom-apis.html).</a> It is the user agents responsibility to expose all relevant content to the platform accessibility api. Alternatively, the user agent must respond to requests for information from APIs. </li>
<li><strong>Examples of Success Criterion 4.1.4 :</strong>
<ul>
<li>In user agents today, an author may inject content into a web page using CSS (generated content). This content is written to the screen and the CSS DOM. The user agent does not expose this generated content from the CSS-DOM (as per CSS recommendation) to the platform accessibility API or to the HTML-DOM. This generated content is non-existent to an assistive technology user. The user agent should expose all information from all DOMs to the platform accessibility API.</li>
<li>
A web page is a compound document containing HTML, MathML, and SVG. Each has a separate DOM. As the user moves through the document, they are moving through multiple DOMs. The transition between DOMs is seamless and transparent to the user and their assistive technology. All of the content is read and all of the interaction is available from the keyboard regardless of the underlying source code or the respective DOM. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.4 :</strong>
<ul>
<li class="proposed-text">www.w3.org/TR/SVG/svgdom.html</li>
<li class="proposed-text">www.w3.org/TR/MathML/chapter8.html</li>
<li class="proposed-text"> www.w3.org/TR/DOM-Level-2-HTML/</li>
<li class="proposed-text">www.w3.org/TR/DOM-Level-2-Style/</li>
<li class="proposed-text"><a href="https://developer.mozilla.org/en/gecko_dom_reference">https://developer.mozilla.org/en/gecko_dom_reference</a></li>
<li class="proposed-text"><a href="http://developer.apple.com/mac/library/documentation/AppleApplications/Conceptual/SafariJSProgTopics/Tasks/DOM.html">http://developer.apple.com/mac/library/documentation/AppleApplications/Conceptual/SafariJSProgTopics/Tasks/DOM.html</a></li>
<li class="proposed-text"><a href="http://msdn.microsoft.com/en-us/library/ms533050%28VS.85%29.aspx"> http://msdn.microsoft.com/en-us/library/ms533050%28VS.85%29.aspx</a></li>
<li class="proposed-text">www.adobe.com/devnet/acrobat/pdfs/access.pdf</li>
<li class="proposed-text">www.w3.org/2004/CDF/</li>
<li class="proposed-text">dev.w3.org/2006/cdf/cdi-framework/</li>
<li class="proposed-text">www.w3.org/TR/CDR/</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-415">4.1.5 Write Access:</h4>
<p class="sc-text"> If the user agent keeps an internal representation of the user content in terms of element structure, relationships between elements, element meaning, or some combination thereof, it must expose this internal representation via an appropriate means (normally by using the platform accessibility architecture or a programmatically available DOM). <span class="level">(Level A)</span></p> <br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.5 :</strong> <br />
If the user can affect the user interface using any form of input, the same affect may be done through programmatic access. It is often more reliable for assistive technology to use the programmatic method of access versus attempting to simulate mouse or keyboard input. </li>
<li><strong>Examples of Success Criterion 4.1.5 :</strong>
<ul>
<li>When the user says the phrase 'Volume 35%' their speech input utility can programmatically set the value of the volume slider to 35%, rather than having to use trial and error by simulating mouse clicks or arrow presses to try to find the 35% point.</li>
<li>"Francois directs his third-party macro utility to set the value of a tri-state check box to "mixed". Even though the control would normally need to be cycled through its states of “on”, “off”, and “mixed”, the macro utility can set the control directly to the desired state.<br />
</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.5 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-416">4.1.6 Properties:</h4><p class="sc-text"> If any of
the following properties are supported by the accessibility platform
architecture, make the properties available to the accessibility platform
architecture: <span class="level">(Level A)</span>
</p><ol type="a">
<li>the bounding dimensions and coordinates of rendered graphical
objects</li>
<li>font family of text </li>
<li>font size of text </li>
<li>foreground color of text </li>
<li>background color of text.</li>
<li>change state/value notifications</li>
<li>selection</li>
<li>highlighting</li>
<li>input device focus</li>
</ol>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.6 :</strong> <br />
These properties are used by assistive technology to create alternative views of the user agent user interface and rendered content as well as providing alternative means for the user to interact with these items.</li>
<li><strong>Examples of Success Criterion 4.1.6 1:</strong>
<ul>
<li>Kiara loads a new version of a popular web browser for the first time. She puts her screen reader into an "explore mode" that lets her review what is appearing on the screen. Her screen reader uses the bounding rectangle of each element to tell her that items from the menu bar all appear on the same horizontal line, which is below the window's title bar.</li>
<li>Kiara is using a screen reader at a telephone call center. The Web application displays caller names in different colors depending on their banking status. Kiara needs to know this information to appropriately respond to each customer immediately, without taking the time to look up their status through other means.</li>
<li>
Max uses a screen magnifier that only shows him a small amount of the screen at one time. He gives it commands to pan through different portions of a Web page, but then can give it additional commands to quickly pan back to positions of interest, such as the text matched by the recent Search operation, text that he previously selected by dragging the mouse, or the text caret, rather than having to manually pan through the document searching for them. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.6 :</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-417">4.1.7 Timely Communication:</h4><p class="sc-text">
For APIs implemented to satisfy the requirements of UAAG 2.0, ensure that programmatic exchanges proceed at a rate such that users do not perceive a delay. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.1.7 :</strong> <br />
Conveying information for accessibility can often involve extensive communication between a user agent, an accessibility API, document object model, assistive technology and end user interaction. The objective is to ensure that the end user does not perceive a delay when interacting with the user agent. </li>
<li><strong>Examples of Success Criterion 4.1.7 :</strong>
<ul>
<li>Bonita accesses her web browser with a speech input program. She navigates to a web page and speaks the name of a link she wants to click. The link is activated with the same speed as it would be if a mouse had been used to click the link.</li>
<li>Arthur is browsing a web page with a screen reader. As he tabs from link to link, the text of each link instantly appears on his braille display.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.1.7 :</strong>
<ul>
<li class="editor-notes">@@ Editors' note: Insert something about performance and classifications.@@</li>
</ul>
</li>
</ul>
<h3 class="guideline"><a name="gl-nested-UA" id="gl-nested-UA"></a><span class="techs-only">Implementing </span>Guideline 4.2 - <span class="principle">Facilitate programmatic access to nested user agents </span>
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-nested-UA">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary42"><strong>Summary</strong>: <span class="editor-notes">@@ Editors' Note: To be written @@</span></p>
<h4 class="sc-title" id="sc-421">4.2.1 Hand-Off Focus<span class="diff-renumber"> [former 1.9.5]</span>: </h4>
<p class="sc-text">The
user agent programmatically notifies any nested user agent(s) (e.g.
plug-ins) when <a class="dfn-instance" href="#def-active-input-focus"
title="definition: active input focus">active input focus</a> moves to a nested agent. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.2.1:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 4.2.1:</strong>
<ul>
<li>A browser plug-in is installed to play a popular media format. When the user tabs to the controls for the plug-in, the user agent notifies the plug-in to handle keyboard interaction.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.2.1:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-422">4.2.2 Retrieve Focus<span class="diff-renumber"> [former 1.9.6, before that 3.11.6]</span>: </h4>
<p class="sc-text">The
user agent programmatically notifies any nested user agent(s) (e.g.
plug-ins) when <a class="dfn-instance" href="#def-active-input-focus"
title="definition: active input focus">active input focus</a> moves to a nested agent. <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.2.2:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 4.2.2:</strong>
<ul>
<li>A browser plug-in is installed to play a popular media format. When the user tabs to the controls for the plug-in, the user agent notifies the plug-in to handle keyboard interaction.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.2.2:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-423">4.2.3 Return Focus<span class="diff-renumber"> [former 1.9.7, before that 3.11.7]</span>: </h4>
<p class="sc-text">At any time, the user agent can retrieve input focus from a nested viewport (including nested viewports that are user agents). <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 4.2.3:</strong> <br />
<span class="proposed-text">T</span></li>
<li><strong>Examples of Success Criterion 4.2.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 4.2.3:</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h2 class="principle"><a name="principle-follow-specs"
id="principle-follow-specs"></a>PRINCIPLE 5: Comply with applicable
specifications and conventions</h2>
<h3 class="guideline"><a name="gl-desktop-access"
id="gl-desktop-access"></a><span class="techs-only">Implementing</span> Guideline 5.1 - Ensure that non-Web-based
functionality is accessible.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-desktop-access">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary51"><strong>Summary</strong>: The browser's own menus, buttons, dialogs, etc. need to meet any accessibility standards for the operating system.</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-511">5.1.1 Non-Web-Based Accessible
<span class="level">(Level A)</span> : </h4>
<p class="sc-text">Non-Web-based user agent user interfaces comply with and
cite the requirements of standards or <a class="termdef" href="#def-operating-environment" title="definition: operating environment">operating environment</a> conventions that
benefit accessibility. <span class="level">(Level A)</span> </p>
<br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.1.1:</strong> <br />
The user should be able to easily discover detailed information about the
user agent's adherence to accessibility standards of the operating
environment or adherence to external accessibility requirements without
installing and testing the accessibility features.</li>
<li><strong>Examples of Success Criterion 5.1.1 :</strong>
<ul>
<li>User agent X lists the platform accessibility tools (high contrast, show
sounds, sticky keys, etc) supported. Additionally, the user agent lists all
of the platform accessibility APIs or other APIs that are supported.
"User Agent X supports the Windows Accessibility API (MSAA) to display
accessibility information and events for its features and web content."</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.1.1:</strong>
<ul>
<li>http://www.microsoft.com/windowsxp/using/accessibility/default.mspx</li>
<li>http://www.apple.com/accessibility/</li>
<li>http://www.linux.org/docs/ldp/howto/Accessibility-HOWTO/linuxos.html</li>
<li>http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2</li>
<li>http://developer.apple.com/ue/accessibility/</li>
<li>http://msdn.microsoft.com/en-us/library/dd373592%28VS.85%29.aspx</li>
<li>http://msdn.microsoft.com/en-us/windows/ee815673.aspx</li>
</ul>
</li>
</ul>
</div>
<div class="applic-notes">
<h4 id="app-note-desktop-access">Applicability Notes:</h4>
<p>This guideline does not apply to Web-based user agent user interfaces, but
does include any parts of Web-based user agents that are non-Web-based (e.g. client-side file uploaders).</p>
</div>
<h3 class="guideline"><a name="gl-obs-env-conventions"
id="gl-obs-env-conventions"></a><span class="techs-only">Implementing </span>Guideline 5.2 - Ensure that Web-based
functionality is accessible.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-obs-env-conventions">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary52"><strong>Summary</strong>: When the browser's menus, buttons, dialogs, etc. are authored in HTML or similar standards, they need to meet W3C's Web Content Accessibility Guidelines.</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-521">5.2.1 Web-Based Accessible <span class="level">(Level A)</span> : </h4><p class="sc-text">User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level "A".
<span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-522">5.2.2 Web-Based Accessible <span class="level">(Level AA)</span> :</h4><p class="sc-text"> User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level
"AA". <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-523">5.2.3 Web-Based Accessible <span class="level">(Level AAA)</span> :</h4><p class="sc-text"> User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level
"AAA". <span class="level">(Level AAA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Guideline 5.2:</strong> <br />
Web-based applications which are intended to replace or enhance a desktop user agent or its functionality, but are in-fact built and rendered using standard Web technologies, are becoming increasingly common. These Web applications, windowless browsers, rich internet applications, HTML5 canvas, etc., perform similar functions to their desktop cousins and so must also conform to the accessibility requirements placed on a desktop user agent.</li>
<li><strong>Examples of Guideline 5.2:</strong>
<ul>
<li>Success criteria 2.7.1 requires that a user agent enable a user to change settings that impact accessibility. In this case we would expect that a Web-Based user agent should also enable a user to change accessibility settings specific to its functionality, which may in some cases enhance or override that of the platform on which it is executing: window-less browser, native operating system, etc.</li>
</ul>
</li>
<li><strong>Related Resources for Guideline 5.2:</strong>
<ul>
<li>WAI-ARIA 1.0 User Agent Implementation Guide</li>
<li>W3C Web Design and Applications Activity</li>
</ul>
</li>
</ul>
</div>
<div class="applic-notes">
<h4 id="app-note-web-access">Applicability Notes:</h4>
<p>This guideline does not apply to non-Web-based user agent user interfaces,
but does include any parts of non-Web-based user agents that are
Web-based (e.g. help systems).</p>
</div>
<h3 class="guideline"><a name="gl-implement-access-features"
class="guideline" id="gl-implement-access-features"><span class="techs-only">Implementing </span>Guideline 5.3</a> - Support
accessibility features of technologies.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-implement-access-features">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary53"><strong>Summary</strong>: Implement the accessibility features of all the technologies you're using, such as supporting the platform's multitasking capabilities and HTML's alt attribute for images. Document your implementation.</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-531">5.3.1 Implement accessibility features of content specs:</h4>
<p class="sc-text">Implement and cite in the conformance claim the accessibility
features of content
specifications. Accessibility features are those that are either <span class="level">(Level A)</span> :</p>
<ul>
<li>identified as such in the specification or</li>
<li>allow authors to satisfy a requirement of WCAG.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.3.1:</strong> <br />
</li>
<li><span class="editor-notes">@@ Editors' Note: add a sentence about the importance of content standards @@</span><br />
If browsers and players don't seamlessly conform to platform accessibility features, then users can't easily take advantage of those features. Software that has versions for different platforms, may have to handle accessibility differently on different platforms or operating systems. In order to show that you have implemented the accessibility features of the platform correctly, these features are identified in the conformance claim.<br />
<br />
The user should be able to easily discover detailed information about the user agent’s adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, and should be able to do so without installing and testing the accessibility features.<br />
<br />
</li>
<li><strong>Examples of Success Criterion 5.3.1 :</strong>
<ul>
<li><span class="editor-notes">[@@ Editors' Note: We need an ARIA example here @@ ]</span> <br />
In the conformance claim [link to conformance section], list the requirements you fully comply with, list the requirements you partially comply with and explain, and list the requirements you do not comply with and explain. Where applicable, this explanations can be general and cover several sections at once. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.3.1:</strong>
<dl>
<dt class="proposed-text">WCAG</dt>
<dt class="proposed-text">HTML</dt>
<dt class="proposed-text">CSS</dt>
<dt class="proposed-text">WAI-ARIA</dt>
</dl></li>
</ul>
</div>
<div class="sc-level">
<h4 class="sc-title" id="sc-532">5.3.2 Implement Accessibility Features of platform: </h4><p class="sc-text">Implement and cite in the conformance claim the accessibility
features of content and platform <a href="#def-Web-Content-Technology">technology</a>
specifications. Accessibility features are those that are either <span class="level">(Level A)</span> :</p>
<ul>
<li>identified as such in the specification or</li>
<li>allow authors to satisfy a requirement of WCAG.</li>
</ul>
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.3.2:</strong> <br />
</li>
<li><span class="editor-notes">@@ Editors' Note: add a sentence about the importance of content standards @@</span><br />
If browsers and players don't seamlessly conform to platform accessibility features, then users can't easily take advantage of those features. Software that has versions for different platforms, may have to handle accessibility differently on different platforms or operating systems. In order to show that you have implemented the accessibility features of the platform correctly, these features are identified in the conformance claim.<br />
<br />
The user should be able to easily discover detailed information about the user agent's adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, platform standards such as MSAA or JAA, and third-party standards such as ISO 9241-171, and should be able to do so without installing and testing the accessibility features.<br />
<br />
</li>
<li><strong>Examples of Success Criterion 5.3.2 :</strong>
<ul>
<li>If you are developing for the Gnome platform, consult the <a href="http://developer.gnome.org/accessibility-devel-guide/">Gnome Accessibility Developers Guide</a>. For example, the Keyboard Focus section states: "Show current input focus clearly at all times. Remember that in controls that include a scrolling element, it is not always sufficient to highlight just the selected element inside that scrolling area, as it may not be visible. " If your program controls focus, make sure you conform to this accessibility guideline for focus. <br />
<br />
In the conformance claim [link to conformance section], list the requirements you fully comply with, list the requirements you partially comply with and explain, and list the requirements you do not comply with and explain. Where applicable, this explanations can be general and cover several sections at once. </li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.3.2:</strong>
<dl>
<dt class="proposed-text"><a name="ref-APPLE-ACCESS" id="ref-APPLE-ACCESS"><strong>[APPLE-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://developer.apple.com/mac/library/documentation/Accessibility/Conceptual/AccessibilityMacOSX/index.html">Introduction to Accessibility Overview</a>," Apple Computer Inc.</dd>
<dt class="proposed-text"><a name="ref-CARBON-ACCESS" id="ref-CARBON-ACCESS"><strong>[CARBON-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://developer.apple.com/legacy/mac/library/documentation/Carbon/Conceptual/MakingAppsAccessible/index.html">Introduction to Accessibility Programming Guidelines for Carbon</a>," Apple Corporation.</dd>
<dt class="proposed-text"><a name="ref-COCOA-ACCESS" id="ref-COCOA-ACCESS"><strong>[COCOA-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://developer.apple.com/mac/library/documentation/Cocoa/Conceptual/Accessibility/index.html">Introduction to Accessibility Programming Guidelines for Cocoa</a>," Apple Corporation.</dd>
<dt class="proposed-text"><a name="ref-EITAAC" id="ref-EITAAC"><strong>[EITAAC]</strong></a></dt>
<dd class="proposed-text">"<a href="http://trace.wisc.edu/docs/eitaac_desktop_software_standards/desktop_software_standards.htm">EITAAC Desktop Software standards</a>," Electronic Information Technology Access Advisory (EITAAC) Committee.</dd>
<dt class="proposed-text"><a name="ref-GNOME-ACCESS" id="ref-GNOME-ACCESS"><strong>[GNOME-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://developer.gnome.org/accessibility-devel-guide/">GNOME Accessibility for Developers</a>," C. Benson, B. Cameron, B. Haneman, S. Snider, P. O'Briain, The GNOME Accessibility Project.</dd>
<dt class="proposed-text"><a name="ref-GNOME-API" id="ref-GNOME-API"><strong>[GNOME-API]</strong></a></dt>
<dd class="proposed-text">"<a href="http://developer.gnome.org/atk/">Gnome Accessibility Toolkit API</a>"</dd>
<dt class="proposed-text"><a name="ref-GNOME-KDE-KEYS" id="ref-GNOME-KDE-KEYS"><strong>[GNOME-KDE-KEYS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www.novell.com/coolsolutions/tip/2289.html">Gnome/KDE Keyboard Shortcuts</a>," Novell Corporation.</dd>
<dt class="proposed-text"><a name="ref-IBM-ACCESS" id="ref-IBM-ACCESS"><strong>[IBM-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www-03.ibm.com/able/guidelines/accesssoftware.html">Software Accessibility</a>," IBM Special Needs Systems.</dd>
<dt class="proposed-text"><a name="ref-IEC-4WD" id="ref-IEC-4WD"><strong>[IEC-4WD]</strong></a></dt>
<dd class="proposed-text">IEC/4WD 61966-2-1: Colour Measurement and Management in Multimedia Systems and Equipment - Part 2.1: Default Colour Space - sRGB. May 5, 1998.</dd>
<dt class="proposed-text"><a name="ref-ISO16071" id="ref-ISO16071"><strong>[ISO-TS-16071]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www.iso.org/iso/catalogue_detail.htm?csnumber=30858">Ergonomics of human-system interaction -- Guidance on accessibility for human-computer interfaces</a>". International Organization for Standardization.</dd>
<dt class="proposed-text"><a name="ref-JAVA-ACCESS" id="ref-JAVA-ACCESS"><strong>[JAVA-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www-306.ibm.com/able/guidelines/java/snsjavag.html">IBM Guidelines for Writing Accessible Applications Using 100% Pure Java</a>," R. Schwerdtfeger, IBM Special Needs Systems.</dd>
<dt class="proposed-text"><a name="ref-JAVA-API" id="ref-JAVA-API"><strong>[JAVA-API]</strong></a></dt>
<dd class="proposed-text">"<a href="http://java.sun.com/j2se/1.5.0/docs/api/javax/accessibility/package-summary.html"> Java Accessibility Package</a>"</dd>
<dt class="proposed-text"><a name="ref-JAVA-CHECKLIST" id="ref-JAVA-CHECKLIST"><strong>[JAVA-CHECKLIST]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www-306.ibm.com/able/guidelines/java/accessjava.html">Java Accessibility Guidelines and Checklist</a>," IBM Special Needs Systems.</dd>
<dt class="proposed-text"><a name="ref-MACOSX-KEYS" id="ref-MACOSX-KEYS"><strong>[MACOSX-KEYS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://support.apple.com/kb/HT1343">Mac OS X keyboard shortcuts</a>," Apple Corporation.</dd>
<dt class="proposed-text"><a name="ref-MS-ENABLE" id="ref-MS-ENABLE"><strong>[MS-ENABLE]</strong></a></dt>
<dd class="proposed-text">"<a href="http://msdn.microsoft.com/en-us/library/ms123402.aspx?missingurl=%2fen-us%2flibrary%2faa286482.aspx">Accessibility for Applications Designers</a>," Microsoft Corporation.</dd>
<dt class="proposed-text"><a name="ref-Windows7-Access" id="ref-Windows7-Access"></a><strong>[MS-WIN7-ACCESS]</strong></dt>
<dd class="proposed-text"><a href="http://www.microsoft.com/downloads/details.aspx?familyid=6E71A995-45E0-4170-8AC2-C1C0E635548D&displaylang=en">"Engineering Software For Accessibility"</a>, Microsoft Corporation.</dd>
<dt class="proposed-text"><a name="ref-MS-KEYS" id="ref-MS-KEYS"><strong>[MS-KEYS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://support.microsoft.com/default.aspx?scid=kb;en-us;q126449">Keyboard shortcuts for Windows</a>," Microsoft Corporation.</dd>
<dt class="proposed-text"><a name="ref-NOTES-ACCESS" id="ref-NOTES-ACCESS"><strong>[NOTES-ACCESS]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www-306.ibm.com/able/guidelines/notes/accessr5.html">Lotus Notes application accessibility</a>," IBM Corporation.</dd>
<dt class="proposed-text"><a name="ref-SUN-DESIGN" id="ref-SUN-DESIGN"><strong>[SUN-DESIGN]</strong></a></dt>
<dd class="proposed-text">"<a href="http://www.sun.com/accessibility/resources.jsp">Designing for Accessibility</a>," Eric Bergman and Earl Johnson. This paper discusses specific disabilities including those related to hearing, vision, and cognitive function. </dd>
<dt class="proposed-text">[Editors' Note: Resource links from Jim - compare and expand]</dt>
<dd class="proposed-text">http://www.microsoft.com/windowsxp/using/accessibility/default.mspx</dd>
<dd class="proposed-text">http://www.apple.com/accessibility/</dd>
<dd class="proposed-text">http://www.linux.org/docs/ldp/howto/Accessibility-HOWTO/linuxos.html</dd>
<dd class="proposed-text">http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2</dd>
<dd class="proposed-text">http://developer.apple.com/ue/accessibility/</dd>
<dd class="proposed-text">http://msdn.microsoft.com/en-us/library/dd373592%28VS.85%29.aspx</dd>
<dd class="proposed-text">http://msdn.microsoft.com/en-us/windows/ee815673.aspx</dd>
</dl></li>
</ul>
</div>
<p class="editor-notes">[@@ Editor's Note: <a href="http://lists.w3.org/Archives/Public/public-uaag2-comments/2011May/0000.html">Suzanne proposed additional SC</a> which are holding on <a href="http://www.w3.org/2011/06/02-ua-minutes.html">action items</a>. @@]]
</p>
<h3 class="guideline"><a name="gl-render-to-spec"
id="gl-render-to-spec"><span class="techs-only">Implementing </span>Guideline 5.4</a> - Render content according to
specification.
<span class="techs-only">[<a href="http://www.w3.org/TR/2011/WD-UAAG20-20110719/Overview.html#gl-render-to-spec">Return to Guideline</a>]</span></h3>
<p class="summary" id="summary54"><strong>Summary</strong>: Render content according to the technology specification, including accessibility features (5.4.1), and let users choose how content types are handled, such as opening embedded images, videos, or documents in separate applications or saving them to disk (5.4.2, 5.4.3).</p>
<div class="sc-level">
<h4 class="sc-title" id="sc-541">5.4.1 Follow Specifications:</h4>
<p class="sc-text"> The user agent renders <a class="dfn-instance" href="#def-content"
title="definition: Content">content</a> according to the <a
href="#def-Web-Content-Technology">technology</a> specification, except where it would actually harm overall accessibility.
<span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.4.1:</strong> <br />
End users and assistive technology products assume that content will be rendered in a predictable fashion. This success criterion ensures that user agents provide this level of predictability. It may be necessary to ignore aspects of the technology specification where they would actually harm, rather than improve, overall accessibility. In these cases user agent developers are encouraged to deviate from those aspects of the standard, and document the decision in their conformance claim. For example, the CSS spec says generated content should not appear in the <a class="dfn-instance"
href="#def-dom" title="definition: Document Object Model">DOM</a>, which may mean that generated content would not be exposed to assistive technology and thus may not be accessible to blind users. User agents should instead expose the generated content through the DOM, and document their decision to ignore that aspect of the specification.</li>
<li><strong>Examples of Success Criterion 5.4.1 :</strong>
<ul>
<li>A user agent implements the WAI-ARIA (Accessible Rich Internet Applications) standard, and the developer follows the "Implementing ARIA" document by mapping ARIA roles and events to the supported platform accessibility infrastructure (MSAA, UIA, ____, etc.). This allows a screen reader that supports the platform infrastructure to correctly support ARIA in the user agent.</li>
<li>An organization creates an optional style sheet that enlarges fonts and adapts all colors for maximum contrast. They can be confident that when their Web site uses this style sheet it will work with any browser because those browsers have implemented CSS according to the CSS specification.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.4.1:</strong>
<ul>
<li><a href="#gl-implement-access-features">Guideline 5.3</a></li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-542">5.4.2 Handle Unrendered
Technologies:</h4>
<p class="sc-text"> If the <a href="#def-user-agent">user agent</a> does
not render a technology, the user can choose a way to handle content
in that technology (e.g. by launching another application or by saving it to
disk). <span class="level">(Level A)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.4.2:</strong> <br />
Users who have disabilities may have fewer options in terms of how they access the information. Information is made available in a variety of ways on the Internet, and at times a specific format may be the only way in which information is available. If the user agent cannot render that format it should let the user access that content through alternate means, such as invoking a third-party renderer or saving the file to the user's hard drive.</li>
<li><strong>Examples of Success Criterion 5.4.2 :</strong>
<ul>
<li>Tracy has low vision and finds it much more convenient to access her bank statement electronically than on paper, even though the electronic version is in a TIFF image, a format that her browser cannot render. In this case, the browser lets her save the image to her hard drive so she can open it in another program.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.4.2</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
<h4 class="sc-title" id="sc-543">5.4.3 Alternative content handlers: </h4>
<p class="sc-text"> The user can select content elements and have them rendered in alternative viewers. <span class="level">(Level AA)</span> </p><br clear="all" class="sc-close" />
<ul class="techs-only">
<li> <strong>Intent of Success Criterion 5.4.3:</strong> <br />
When accessing media content on the Web, users with disabilities sometimes find they have a richer or more accessible experience in a third-party application than using the browser's built-in facilities. In these cases they want to be able to navigate to content in their browser, then save that content to their disk or launch it in a third-party application. </li>
<li><strong>Examples of Success Criterion 5.4.3 :</strong>
<ul>
<li>A browser supports the VIDEO tag and adds its own play and pause controls, but George prefers to view the video content in a third-party application that provides much more sophisticated navigation controls such as bookmarks, skip-forward and backwards, and the ability to speed playback without increasing pitch of the audio track. In the browser, he right-clicks on the video to display a context menu, and from that chooses "Open in…", and then chooses his preferred video player. The browser launches the player to show that video file in the browser's cache folder. The browser saves the video to a temporary location on the user's disks (or uses one already in its cache folder), then launches the player to show that file.<br />
<br />
In the case of streaming video that cannot be saved to disk, the browser launches the external viewer, passing it the URL to the online video.</li>
</ul>
</li>
<li><strong>Related Resources for Success Criterion 5.4.3</strong>
<ul>
<li>To be written</li>
</ul>
</li>
</ul>
</div>
<div class="applic-notes">
<h4 id="app-note-render-to-spec">Applicability Note:</h4>
<p>When a rendering requirement of another specification contradicts a
requirement of UAAG 2.0, the user agent may disregard the rendering
requirement of the other specification and still satisfy this guideline.</p>
</div>
<h2><a name="conformance" id="conformance"></a>Conformance</h2>
<p>This section is normative.</p>
<p>Conformance means that the user agent satisfies the success criteria
defined in the guidelines section. This conformance section describes
conformance and lists the conformance requirements.</p>
<h3><a name="conformance-require" id="conformance-require"></a>Conformance Requirements</h3>
<p> In order for a Web page to conform to UAAG 2.0, one of the following levels of conformance is met
in full.</p>
<ul>
<li>Level A: For Level A conformance (the minimum level of conformance), the
user agent satisfies all the Level A Success Criteria.</li>
<li>Level AA: For Level AA conformance, the user agent satisfies all the
Level A and Level AA Success Criteria.</li>
<li>Level AAA: For Level AAA conformance, the user agent satisfies all the
Level A, Level AA and Level AAA Success Criteria.</li>
</ul>
<p> Note 1: Although conformance can only be achieved at the stated levels,
developers are encouraged to report (in their claim) any progress toward
meeting success criteria from all levels beyond the achieved level of
conformance. </p>
<h3><a name="conformance-claims" id="conformance-claims"></a>Conformance Claims (Optional)</h3>
<p>If a conformance claim is made, the conformance claim must meet the
following conditions and include the following information (user agents
can conform to UAAG 2.0 without making a claim):</p>
<h3><a name="conformance-conditions" id="conformance-conditions"></a>Conditions on Conformance Claims</h3>
<ul>
<li>At least one version of the conformance claim must be published on the
web as a document meeting level "A" of WCAG 2.0. A suggested metadata
description for this document is "UAAG 2.0 Conformance Claim".</li>
<li>Whenever the claimed conformance level is published (e.g. product
information website), the URI for the on-line published version of the
conformance claim must be included. </li>
<li>The existence of a conformance claim does not imply that the W3C has
reviewed the claim or assured its validity. </li>
<li>Claimants may be anyone (e.g. user agent developers, journalists, other
third parties).</li>
<li>Claimants are solely responsible for the accuracy of their claims
(including claims that include products for which they are not
responsible) and keeping claims up to date.</li>
<li>Claimants are encouraged to claim conformance to the most recent version
of the User Agent Accessibility Guidelines Recommendation. </li>
</ul>
<h3><a name="conformance-req-components" id="conformance-req-components"></a>Required Components of an UAAG 2.0 Conformance Claim</h3>
<ol>
<li>Claimant name and affiliation.</li>
<li>Date of the claim. </li>
<li>Conformance level satisfied.</li>
<li>User agent information: The name of the user agent and sufficient
additional information to specify the version (e.g. vendor name,
version number (or version range), required patches or updates, human
language of the user interface or documentation). <br />
Note: If the user agent is a collection of software components (e.g. a
browser and extentions or plugins), then the name and version information must be provided
separately for each component, although the conformance claim will treat
them as a whole. As stated above, the Claimant has sole responsibility
for the conformance claim, not the developer of any of the software
components.</li>
<li>Included Technologies: A list of the web content technologies
(including version numbers) rendered by the user agent that the Claimant
is including in the conformance claim. By including a web content
technology, the Claimant is claiming that the user agent meets the
requirements of UAAG 2.0 during the rendering of web content using that
web content technology. <br />
Note 1: Web content technologies may be a combination of constituent web
content technologies. For example, an image technology (e.g. PNG) might
be listed together with a markup technology (e.g. HTML) since web
content in the markup technology is used make web content in the image
technology accessible (e.g. a PNG graph is made accessible using an
HTML table).</li>
<li>Excluded Technologies: A list of any web content technologies produced
by the the user agent that the Claimant is excluding from the
conformance claim. The user agent is not required to meet the
requirements of UAAG 2.0 during the production of the web content
technologies on this list.</li>
<li>Declarations: For each success criterion:
A declaration of whether or not the success criterion has been
satisfied; or <br />
A declaration that the success criterion is not applicable and a
rationale for why not.</li>
<li>Platform(s): The platform(s) upon which the user agent was evaluated:
For user agent platform(s) (used to evaluate web-based user agent user
interfaces): provide the name and version information of the user agent(s).
For platforms that are not user agents (used to evaluate non-web-based
user agent user interfaces) provide: The name and version information of
the platform(s) (e.g. operating system, etc.) and the the name and
version of the platform accessibility architecture(s) employed.</li>
</ol>
<h3><a name="conformance-opt-components" id="conformance-opt-conponents"></a>Optional Components of an UAAG 2.0 Conformance Claim</h3>
<p>A description of how the UAAG 2.0 success criteria were met where this
may not be obvious. </p>
<h3><a name="conformance-progress" id="conformance-progress"></a>"Progress Towards Conformance" Statement</h3>
<p>Developers of user agents that do not yet conform fully to a particular
UAAG 2.0 conformance level are encouraged to publish a statement on
progress towards conformance. The progress statement is the same as a
conformance claim except an UAAG 2.0
conformance level that is being progressed towards, rather than one
already satisfied, and report progress on success criteria not yet
met. Authors of "Progress Towards Conformance" Statement are solely
responsible for the accuracy of their statements. Developers are
encouraged to provide expected timelines for meeting outstanding success
criteria within the Statement. </p>
<h3><a name="conformance-disclaimer" id="conformance-disclaimer"></a>Disclaimer</h3>
<p>Neither W3C, WAI, nor UAWG take any responsibility for any aspect or
result of any UAAG 2.0 conformance claim that has not been published
under the authority of the W3C, WAI, or UAWG. </p>
<h2><a name="glossary" id="glossary">Appendix A: Glossary</a></h2>
<p>This glossary is <a class="dfn-instance" href="#def-normative"
title="definition: Normative">normative</a>.</p>
<div class="noprint">
<map name="navbar-glossary" class="navbar" id="navbar-glossary">
<p><a href="#a">a</a> · b · <a href="#c">c</a> · <a href="#d">d</a> ·
<a href="#e">e</a> · <a href="#f">f</a> · <a href="#g">g</a> · <a
href="#h">h</a> · <a href="#i">i</a> · j · k · l · m · <a
href="#n">n</a> · <a href="#o">o</a> · <a href="#p">p</a> · q · <a
href="#r">r</a> · <a href="#s">s</a> · <a href="#t">t</a> · <a
href="#u">u</a> · <a href="#v">v</a> · <a href="#w">w</a> · x · y ·
z</p>
</map>
</div>
<dl id="term-list">
<dt><a name="a" id="a"></a><dfn>accelerator key</dfn></dt>
<dd>see <a href="#def-accelerator-key"><dfn>keyboard command</dfn></a></dd>
<dt class="glossary"><a name="def-activate"
id="def-activate"><dfn>activate</dfn></a></dt>
<dd class="glossary">To carry out the behaviors associated
with an <a class="dfn-instance" href="#def-enabled-element"
title="definition: Enabled element">enabled element</a> in the rendered
content or a component of the <a class="dfn-instance" href="#def-ua-ui"
title="definition: user agent user interface">user agent user
interface</a>.</dd>
<dt><dfn>active input focus</dfn></dt>
<dd>see <a href="#def-focus"><dfn>focus</dfn></a></dd>
<dt><dfn>active selection</dfn></dt>
<dd>see <a href="#def-focus"><dfn>focus</dfn></a></dd>
<dt class="glossary"><a name="def-conditional-content"
id="def-conditional-content"><dfn>alternative content</dfn></a></dt>
<dd><a href="#def-content"
title="definition: Content">Content</a> that can be used in place of default content that may not be universally accessible. Alternative content fulfills the same purpose as the original content. Examples include text alternatives for non-text content, captions for audio, audio descriptions for video, sign language for audio, media alternatives for time-based media. See <a href="http://www.w3.org/TR/WCAG20/">WCAG</a> for more information. </dd>
<dt class="glossary"><a name="def-conditional-content-stack"
id="def-conditional-content-stack"></a><dfn>alternative content
stack</dfn></dt>
<dd class="glossary">A set of <a
href="#def-conditional-content">alternative content</a> items. The items may be mutually exclusive (e.g.
regular contrast graphic vs. high contrast graphic) or non-exclusive
(e.g. caption track that can play at the same time as a sound
track).</dd>
<dt class="glossary"><a name="def-animation"
id="def-animation"><dfn>animation</dfn></a></dt>
<dd class="glossary">Graphical <a href="#def-content"
title="definition: Content">content</a> rendered to automatically change over time, giving the user a visual perception of movement. Examples include video, animated images, scrolling text, programmatic animation (e.g. moving or replacing rendered objects). </dd>
<dt class="glossary"> </dt>
<dt class="glossary"><a name="def-api" id="def-api"><dfn>application
programming interface (API)</dfn></a>, <a name="def-conventional-io-api"
id="def-conventional-io-api"><dfn>(conventional input/output/device
<acronym>API</acronym></dfn></a>)</dt>
<dd class="glossary">An application programming interface (<acronym
title="application programming interface">API</acronym>) defines how
communication may take place between applications.</dd>
<dt class="glossary"><a name="def-assistive-technology"
id="def-assistive-technology"><dfn>assistive technology</dfn></a></dt>
<dd class="glossary">An assistive
technology:
<ol>
<li>relies on services (such as retrieving <a class="dfn-instance"
href="#def-web-resource" title="definition: Web resource">Web
resources</a> and parsing markup) provided by one or more other
"host" user agents. Assistive technologies communicate data and
messages with host user agents by using and monitoring <a
class="dfn-instance" href="#def-api"
title="definition: Application Programming Interface (API)">APIs</a>.</li>
<li>provides services beyond those offered by the host user agents to
meet the requirements of users with disabilities. Additional
services include alternative renderings (e.g. as synthesized
speech or magnified content), alternative input methods (e.g.
voice), additional navigation or orientation mechanisms, and
content transformations (e.g. to make tables more accessible).</li>
</ol>
<p>Examples of assistive technologies that are important in the context
of UAAG 2.0 include the following:</p>
<ul>
<li>screen magnifiers, which are used by people with visual
disabilities to enlarge and change colors on the screen to improve
the visual readability of rendered text and images.</li>
<li>screen readers, which are used by people who are blind or have
reading disabilities to read textual information through
synthesized speech or braille displays.</li>
<li>voice recognition software, which are used by some people who have
physical disabilities to simulate the keyboard and mouse.</li>
<li>alternative keyboards, which are used by some people with
physical disabilities to simulate the keyboard and mouse.</li>
<li>alternative pointing devices, which are used by some people with
physical disabilities to simulate mouse pointing and button
activations.</li>
</ul>
</dd>
<dd class="glossary">Beyond UAAG 2.0, assistive technologies consist
of software or hardware that has been specifically designed to assist
people with disabilities in carrying out daily activities. These
technologies include wheelchairs, reading machines, devices for
grasping, text telephones, and vibrating pagers. For example, the
following very general definition of "assistive technology device"
comes from the (U.S.) Assistive Technology Act of 1998 <cite><a
href="#ref-AT1998"
title="Link to reference AT1998">[AT1998]</a></cite>:
<blockquote>
<p>Any item, piece of equipment, or product system, whether acquired
commercially, modified, or customized, that is used to increase,
maintain, or improve functional capabilities of individuals with
disabilities.</p>
</blockquote>
</dd>
<dt class="glossary"><a name="def-audio"
id="def-audio"><dfn>audio</dfn></a></dt>
<dd class="glossary">The technology of sound reproduction. Audio can be created synthetically (including speech synthesis), streamed from a live source (such as a radio broadcast), or recorded from real world sounds.</dd>
<dt class="glossary"> </dt>
<dt class="glossary"><a name="def-audio-description"
id="def-audio-description"><dfn>audio description</dfn></a> - (described video, video description or descriptive narration)</dt>
<dd>An equivalent alternative that takes the form of narration added to
the <a href="#def-audio">audio</a> to describe important visual details
that cannot be understood from the main soundtrack alone. Audio
description of video provides information about actions, characters,
scene changes, on-screen text, and other visual content. In standard
audio description, narration is added during existing pauses in
dialogue. In <a id="def-Auditory-Description-Extended"
name="def-Auditory-Description-Extended"><dfn>extended audio
description</dfn>, </a>the video is paused so that there is time to add
additional description.</dd>
<dt><dfn><a id="def-author" name="def-author"></a>authors</dfn></dt>
<dd>The people who have worked either alone or collaboratively to create
the content (e.g. content authors, designers, programmers,
publishers, testers).</dd>
<dt><a name="def-author-styles" id="def-author-styles"
class="glossary"><dfn>author styles</dfn></a></dt>
<dd class="glossary"><a class="dfn-instance"
href="#def-Properties-and-Values"
title="definition: Properties, values, and defaults">Style property
values</a> that are set by the author as part of the <a href="#def-content"
title="definition: Content">content</a>. </dd>
<dt><a name="def-background-images"
id="def-background-images"></a>background images</dt>
<dd class="sc-txt">Images that are rendered on the <a
class="dfn-instance" href="#def-base-background"
title="definition: Base Background">base background</a>.</dd>
<dt><a name="def-base-background" id="def-base-background"></a><dfn>base
background</dfn></dt>
<dd>The background of the content as a whole, such that
no content may be layered behind it. In graphics applications, the base
background is often referred to as the canvas.).</dd>
<dt><a name="def-blinking-text" id="def-blinking-text"></a><dfn>blinking
text</dfn></dt>
<dd>Text whose visual rendering alternates between visible and invisible
at any rate of change.</dd>
<dt class="glossary"><a name="c" id="c"></a><a name="def-captions"
id="def-captions"><dfn>captions</dfn></a> (caption)</dt>
<dd>An equivalent alternative that takes the form of text presented and synchronized with <em>time-based</em> media to provide not only the speech, but also non-speech information conveyed through sound, including meaningful sound effects and identification of speakers. In some
countries, the term "subtitle" is used to refer to dialogue only and
"captions" is used as the term for dialogue plus sounds and speaker
identification. In other countries, "subtitle" (or its translation) is
used to refer to both. <dfn>Open captions</dfn> are captions that are
always rendered with a visual track; they cannot be turned off.
<dfn>Closed captions</dfn> are captions that may be turned on and off.
The captions requirements of UAAG 2.0 assume that the user agent
can <a class="dfn-instance" href="#def-recognize"
title="definition: Recognize">recognize</a> the captions as such.<br />
<strong>Note:</strong> Other terms that include the word "caption" may
have different meanings in UAAG 2.0. For instance, a "table
caption" is a title for the table, often positioned graphically above
or below the table. In UAAG 2.0, the intended meaning of "caption"
will be clear from context.</dd>
<dt class="glossary"><a name="def-collated-text-transcript"
id="def-collated-text-transcript"><dfn>collated text
transcript</dfn></a></dt>
<dd class="glossary">A collated text transcript is a <a
class="dfn-instance" href="#def-text-eq"
title="definition: text equivalent">text equivalent</a> of a movie or
other animation. It is the combination of the <a
class="dfn-instance" href="#def-text-transcript"
title="definition: Text transcript">text transcript</a> of the <a
class="dfn-instance" href="#def-audio-track"
title="definition: Audio track">audio track</a> and the text equivalent
of the <a class="dfn-instance" href="#def-visual-track"
title="definition: Visual track">visual track</a>. For example, a
collated text transcript typically includes segments of spoken dialogue
interspersed with text descriptions of the key visual elements of a
presentation (actions, body language, graphics, and scene changes). See
also the definitions of <a class="dfn-instance"
href="#def-text-transcript" title="definition: Text transcript">text
transcript</a> and <a class="dfn-instance"
href="#def-audio-description"
title="definition: Audio description">audio description</a>. Collated
text transcripts are essential for people who are deaf-blind.</dd>
<dt class="glossary"> </dt>
<dd class="glossary"> </dd>
<dt class="glossary"><a name="def-content"
id="def-content"><dfn>content (web content)</dfn></a></dt>
<dd class="glossary">Information and sensory experience to be communicated to the user by means of a user agent, including code or markup that defines the content's structure, presentation, and interactions [adapted from <a href="http://www.w3.org/TR/WCAG20/">WCAG 2.0</a>]
<p><a name="def-empty-content" id="def-empty-content"><dfn>empty
content</dfn></a> (which may be <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>) is
either a null value or an empty string (e.g. one that is zero
characters long). For instance, in HTML, <code>alt=""</code> sets the
value of the <code>alt</code> attribute to the empty string. In some
markup languages, an element may have empty content (e.g. the
<code>HR</code> element in HTML).</p>
</dd>
<dt><dfn>cursor</dfn></dt>
<dd>see <a href="#def-focus"><dfn>focus</dfn></a></dd>
<dt><a name="d" id="d"></a><dfn>default</dfn></dt>
<dd>see <a href="#def-Properties-and-Values"><dfn>properties</dfn></a></dd>
<dt class="glossary"><a name="def-direct-command" id="def-direct-command"></a><dfn>direct command</dfn>, <a name="def-direct-navigation" id="def-direct-navigation"></a><dfn>direct navigation command</dfn>, <a name="def-direct-activation" id="def-direct-activation"></a><dfn>direct activation command</dfn>, <a name="def-linear-navigation" id="def-linear-navigation"></a><dfn>linear navigation command</dfn>
, <a name="def-spacial-command" id="def-spacial-command"></a><dfn>spacial (directional) command</dfn>, <a name="def-structural-navigation" id="def-structural-navigation"></a><dfn>structural navigation command</dfn></dt>
<dd>direct navigation commands move focus to a specified item regardless of which currently has the focus</dd>
<dd>direct activation commands activate a specified item regardless of which currently has the focus; they may move the focus to the item before immediately activating it</dd>
<dd>linear navigation commands (sometimes called logical or sequential navigation commands) move forwards and backwards through a list of items</dd>
<dd>structural navigation commands move forwards, backwards, up and down a hierarchy</dd>
<dd>spatial commands (sometimes called directional commands), require the user to be cognizant of the spatial arrangement of items on the screen:
<ul><li>spatial navigation commands move from one item to another based on direction on the screen</li>
<li>spatial manipulation commands resize or reposition an item on the screen</li></ul></dd>
<dt class="glossary">
<a name="def-doc-char-set" id="def-doc-char-set"><dfn>document character set</dfn></a></dt>
<dd class="glossary">The internal representation of data in the source content by a user agent.</dd>
<dt class="glossary">
<a name="def-document-object"
id="def-document-object"><dfn>document object</dfn></a>, <a name="def-dom"
id="def-dom"><dfn>(Document Object Model</dfn></a>, <acronym title="Document Object Model">DOM</acronym>)</dt>
<dd class="glossary">The Document Object Model is a platform- and language-neutral interface that allows programs and scripts to dynamically access and update the content, structure and style of documents. The document can be further processed and the results of that processing can be incorporated back into the presented page. This is an overview of DOM-related materials here at W3C and around the web:
<a href="http://www.w3.org/DOM/#what">http://www.w3.org/DOM/#what</a>.</dd>
<dt class="glossary"><a name="def-document-source"
id="def-document-source"><dfn>document source</dfn></a>, <a
name="def-text-source" id="def-text-source"><dfn>(text source)</dfn></a></dt>
<dd class="glossary">Text the user agent renders upon user request to view the source of specific viewport content (e.g. selected content, frame, page).</dd>
<dt class="glossary"><a name="def-documentation"
id="def-documentation"><dfn>documentation</dfn></a></dt>
<dd class="glossary">Any information that supports the use of a user agent. This information may be found, for example, in manuals, installation instructions, the help system, and tutorials. Documentation may be distributed (e.g. as files installed as part of the installation, some parts may be delivered on CD-ROM, others on the Web). See <a
href="#gl-doc-access-features">guideline 5.3</a> for information about
documentation.</dd>
<dt class="glossary"><a name="e" id="e"></a><a name="def-element"
id="def-element"><dfn>element</dfn></a>, <a name="def-element-type"
id="def-element-type"><dfn>element type</dfn></a></dt>
<dd class="glossary">UAAG 2.0 uses the terms "element" and "element
type" primarily in the sense employed by the XML 1.0 specification
(<cite><a href="#ref-XML"
title="Link to reference XML">[XML]</a></cite>, section 3): an element
type is a syntactic construct of a document type definition (DTD) for
its application. This sense is also relevant to structures defined by
XML schemas. UAAG 2.0 also uses the term "element" more generally
to mean a type of content (such as video or sound) or a logical
construct (such as a header or list).</dd>
<dt><dfn>empty content </dfn></dt>
<dd>see <a href="#def-content"><dfn>content</dfn></a></dd>
<dt class="glossary"><a name="def-enabled-element"
id="def-enabled-element"><dfn>enabled element</dfn></a>, <a
name="def-disabled-element" id="def-disabled-element"><dfn>disabled
element</dfn></a></dt>
<dd class="glossary">
An <a href="#def-element">element</a> with associated behaviors that can be activated through the user interface or through an <a
class="dfn-instance" href="#def-api"
title="definition: Application Programming Interface (API)">API</a>. The set of elements that a user agent enables is generally derived from, but is not limited to, the set of <a class="dfn-instance"
href="#def-element"
title="definition: Interactive element">elements</a> defined by implemented markup languages. A disabled element is a potentially enabled element that is not currently available for activation (e.g. a "grayed out" menu item).</dd>
<dt class="glossary"><a name="def-equivalent"
id="def-equivalent"><dfn>equivalent alternative</dfn></a></dt>
<dd class="glossary">Acceptable substitute content that a user may not be able to access. An equivalent alternative fulfills essentially the same function or purpose as the original content upon presentation:
<ul>
<li>text alternative: text that is available via the <a class="termdef" href="#def-operating-environment" title="definition: operating environment">operating environment</a> that is used in place of non-text content (e.g. text equivalents for images, text transcripts for audio tracks, or collated text transcripts for a movie). [from <a href="http://www.w3.org/TR/WCAG20/">WCAG 2.0</a>]</li>
<li>full text alternative for synchronized media including any interaction: document including correctly sequenced text descriptions of all visual settings, actions, speakers, and non-speech sounds, and transcript of all dialogue combined with a means of achieving any outcomes that are achieved using interaction (if any) during the synchronized media. [from <a href="http://www.w3.org/TR/WCAG20/">WCAG 2.0</a>]</li>
<li>synchronized alternatives: present essential audio information visually (i.e. captions) and essential video information in an auditory manner (i.e. audio descriptions).
[from <a href="http://www.w3.org/TR/ATAG20/">ATAG 2.0</a>] </li>
</ul>
</dd>
<dt class="glossary"><a name="def-event" id="def-event"><dfn>events and
scripting, event handler, event type</dfn></a></dt>
<dd class="glossary">User agents often perform a task when an event
having a particular "event type" occurs, including a user interface
event, a change to content, loading of content, or a request from the
<a class="dfn-instance" href="#def-operating-environment"
title="definition: Operating environment">operating environment</a>.
Some markup languages allow authors to specify that a script, called an
<a name="def-event-handler" id="def-event-handler"><dfn>event
handler</dfn></a>, be executed when an event of a given type occurs. An
event handler is <a name="def-explicit-handler"
id="def-explicit-handler"><dfn>explicitly associated with an
element</dfn></a> through scripting, markup or the <a href="#def-dom"
><acronym title="Document Object Model">DOM</acronym></a>. </dd>
<dt class="glossary"><a name="def-user-request"
id="def-user-request"><dfn>explicit user request</dfn></a></dt>
<dd class="glossary">An interaction by the user through the <a class="dfn-instance"
href="#def-ua-ui" title="definition: user agent user interface">user
agent user interface</a>, the <a
class="dfn-instance" href="#def-focus"
title="definition: Focus">focus</a>, or the <a class="dfn-instance"
href="#def-selection" title="definition: Selection">selection</a>. User requests are made, for example, through <a class="dfn-instance"
href="#def-ui-control" title="definition: user interface control">user
agent user interface controls</a> and <a href="#def-keyboard-command" title="definition: keyboard command">keyboard commands</a>. Some examples of explicit user requests include when the user selects "New viewport," responds "yes" to a prompt in the user agent's user interface, configures the user agent to behave in a certain way, or changes the selection or focus with the keyboard or pointing device. <strong>Note:</strong> Users can make errors when interacting with the user agent. For example, a user may inadvertently respond "yes" to a prompt instead of "no." This type of error is considered an explicit user request. </dd>
<dt class="glossary"><a name="f" id="f"></a><a name="def-current-focus" id="def-current-focus"></a><a name="def-content-focus" id="def-content-focus"></a><a name="def-focus"
id="def-focus"><dfn>focus</dfn></a> (active input focus, active selection, cursor, focus cursor, focusable element, highlight, inactive input focus, inactive selection, input focus, keyboard focus, pointer, pointing device focus, selection, split focus, text cursor) </dt>
</dl>
<p class="handle"><strong>Hierarchical Summary of some focus terms</strong></p>
<ul><li>Input Focus (active/inactive)
<ul><li>Keyboard Focus (active/inactive)
<ul><li> Cursor (active/inactive)
<ul><li>Focus cursor (active/inactive)</li>
<li>Text cursor (active/inactive)</li></ul>
</li></ul>
</li>
<li>Pointing device focus (active/inactive)
<ul><li>Pointer</li></ul>
</li>
</ul>
</li>
</ul>
<dl>
<dt class="glossary"><a name="def-active-input-focus" id="def-active-input-focus"><dfn>active input focus</dfn></a></dt>
<dd>The <a href="#def-input-focus">input focus</a> location in the active <a href="#def-viewport">viewport</a>. The active focus is in the active viewport, while the inactive input focus is the inactive viewport. The <a href="#def-active-input-focus">active input focus</a> is usually visibly indicated. In UAAG 2.0 "active input focus" generally refers to the active keyboard input focus. <span class="editor-notes">@@ Editors' Note: this term is not used in the document other than the glossary.@@</span></dd>
<dt class="glossary"><a name="def-active-selection" id="def-active-selection"></a><dfn>active selection</dfn></dt>
<dd>The selection that will currently be affected by a user command, as opposed to selections in other viewports, called inactive selections, which would not currently be affected by a user command. <span class="editor-notes">@@ Editors' Note: this term is not used in the document other than the glossary.@@</span></dd>
<dt><dfn>conform</dfn></dt>
<dd>see <a href="#def-support"><dfn>support</dfn></a></dd>
<dt class="glossary"><a name="def-cursor" id="def-cursor"></a><dfn>cursor</dfn></dt>
<dd>Visual indicator showing where keyboard input will occur. There are two types of cursors: <a href="#def-focus-cursor">focus cursor</a> (e.g. the dotted line around a button) and <a href="#def-text-cursor">text cursor</a> (e.g. the flashing vertical bar in a text field, also called a 'caret'). Cursors are active when in the active viewport, and inactive when in an inactive viewport. </dd>
<dt class="glossary"><a name="def-focus-cursor" id="def-focus-cursor"></a><dfn>focus cursor</dfn></dt>
<dd>Indicator that <a href="#def-highlight">highlights</a> a user interface element to show that it has <a href="#def-keyboard-focus">keyboard focus</a>, e.g. a dotted line around a button, or brightened title bar on a window. There are two types of cursors: focus cursor (e.g. the dotted line around a button) and <a href="">text cursor</a> (e.g. the flashing vertical bar in a text field).</dd>
<dt class="glossary"><a name="def-focusable-element" id="def-focusable-element"></a><dfn>focusable element</dfn></dt>
<dd>Any element capable of having <a href="#def-input-focus">input focus</a>, e.g. link, text box, or menu item. In order to be accessible and fully usable, every focusable element should take <a href="#def-keyboard-focus">keyboard focus</a>, and ideally would also take <a href="#def-pointing-device-focus">pointer focus</a>.</dd>
<dt class="glossary"><a name="def-highlight-focus" id="def-highlight-focus"></a><a name="def-highlight" id="def-highlight"></a><dfn>highlight, highlighted, highlighting</dfn></dt>
<dd>Emphasis indicated through the user interface. For example, user agents highlight content that is selected,focused, or matched by a search operation. Graphical highlight mechanisms include dotted boxes, changed colors or fonts, underlining, magnification, and reverse video. Synthesized speech highlight mechanisms include alterations of voice pitch and volume ("speech prosody"). User interface items may also be highlighted, for example a specific set of foreground and background colors for the title bar of the active window. Content that is highlighted may or may not be a <a href="#def-selection">selection</a>.</dd>
<dt class="glossary"><a name="def-inactive-input-focus" id="def-inactive-input-focus"></a><dfn>inactive input focus</dfn></dt>
<dd>An input focus location in an inactive viewport such as a background window or pane. The inactive input focus location will become the active input focus location when input focus returns to that viewport. An inactive input focus may or may not be visibly indicated. </dd>
<dt class="glossary"><a name="def-inactive-selection" id="def-inactive-selection"></a><dfn>inactive selection</dfn></dt>
<dd>A selection that does not have the <a href="#def-input-focus">input focus</a> and thus does not take input events.</dd>
<dt class="glossary"><a name="def-input-focus" id="def-input-focus"></a><dfn>input focus</dfn></dt>
<dd>The place where input will occur if a viewport is active. Examples include keyboard focus and pointing device focus. Input focus can also be active (in the active viewport) or inactive (in an inactive viewport). </dd>
<dt class="glossary"><a name="def-keyboard-focus" id="def-keyboard-focus"></a><dfn>keyboard focus</dfn></dt>
<dd>The screen location where keyboard input will occur if a viewport is active. Keyboard focus can be active (in the active viewport) or inactive (in an inactive viewport). </dd>
<dt class="glossary"><a name="def-pointer" id="def-pointer"></a><dfn>pointer</dfn></dt>
<dd>Visual indicator showing where pointing device input will occur. The indicator can be moved with a pointing device or emulator such as a mouse, pen tablet, keyboard-based mouse emulator, speech-based mouse commands, or 3-D wand. A pointing device click typically moves the <a href="#def-input-focus">input focus</a> to the pointer location. The indicator may change to reflect different states.When touch screens are used, the "pointing device" is a combination of the touch screen and the user's finger or stylus. On most systems there is no pointer (on-screen visual indication) associated with this type of pointing device. </dd>
<dt class="glossary"><a name="def-pointing-device-focus" id="def-pointing-device-focus"></a><dfn>pointing device focus</dfn></dt>
<dd>The screen location where pointer input will occur if a viewport is active. There can be multiple pointing device foci for example when using a screen sharing utility there is typically one for the user's physical mouse and one for the remote mouse. <span class="editor-notes">@@ Editors' Note: this term is not used in the document other than the glossary.@@</span></dd>
<dt class="glossary"><a name="def-selection" id="def-selection"></a><dfn>selection</dfn></dt>
<dd>A user agent mechanism for identifying a (possibly empty) range of content that will be the implicit source or target for subsequent operations. The selection may be used for a variety of purposes, including for cut-and-paste operations, to designate a specific element in a document for the purposes of a query, and as an indication of point of regard (e.g. the matched results of a search may be automatically selected). The selection should be <a href="#def-highlight">highlighted</a> in a distinctive manner. On the screen, the selection may be highlighted in a variety of ways, including through colors, fonts, graphics, and magnification. When rendered using synthesized speech, the selection may be highlighted through changes in pitch, speed, or prosody. </dd>
<dt class="glossary"><a name="def-split-focus" id="def-split-focus"></a><dfn>split focus</dfn></dt>
<dd>A state when the user could be confused because the input focus is separated from something it is usually linked to, such as being at a different place than the selection or similar highlighting, or has been scrolled outside of the visible portion of the viewport. <span class="editor-notes">@@ Editors' Note: this term is not used in the document other than the glossary.@@</span></dd>
<dt class="glossary"><a name="def-text-cursor" id="def-text-cursor"></a><dfn>text cursor</dfn></dt>
<dd>Indicator showing where keyboard input will occur in text (e.g. the flashing vertical bar in a text field, also called a caret).</dd>
<dt class="glossary"><span class="editor-notes">@@ Editor's Note: Need to find the hrefs to these definitions and fix them. @@</span> </dt>
<dt class="glossary"><a name="g" id="g"></a><a name="def-global-configuration"></a><dfn>globally, global configuration</dfn></dt>
<dd class="editor-notes">@@ Editors' Note: Needs to be written@@</dd>
<dt class="glossary"><a name="def-graphical"
id="def-graphical"><dfn>graphical</dfn></a></dt>
<dd class="glossary">Information (e.g. text, colors, graphics, images, and animations)
rendered for visual consumption.</dd>
<dt class="glossary"><a name="h" id="h"></a><dfn>highlight, highlighted, highlighting</dfn></dt>
<dd>see <a href="#def-highlight-focus"><dfn>focus</dfn></a></dd>
<dt class="glossary"><a name="i" id="i"></a><a name="def-image"
id="def-image"><dfn>image</dfn></a></dt>
<dd class="glossary">Pictorial content that is static (i.e. not moving or changing). See also the definition of <a class="dfn-instance"
href="#def-animation" title="definition: Animation">animation</a>.</dd>
<dt><dfn>implement</dfn></dt>
<dd>see <a href="#def-support"><dfn>support</dfn></a></dd>
<dt class="glossary"><a name="def-important-elements"
id="def-important-elements"><dfn>important elements</dfn></a></dt>
<dd class="glossary">This specification intentionally does not identify
which "important elements" must be navigable because this will vary by
specification. What constitutes "efficient navigation" may depend on a
number of factors as well, including the "shape" of content (e.g.
sequential navigation of long lists is not efficient) and desired
granularity (e.g. among tables, then among the cells of a given
table). Refer to the Implementing document [Implementing UAAG 2.0] for information
about identifying and navigating important elements. <span class="editor-notes">@@ Editors' Note: Update links</span></dd>
<dt><dfn>inactive input focus</dfn></dt>
<dd>see <a href="#def-inactive-input-focus"><dfn>focus</dfn></a></dd>
<dt><dfn>inactive selection</dfn></dt>
<dd>see <a href="#def-inactive-selection"><dfn>focus</dfn></a></dd>
<dt><dfn>informative (non-normative)</dfn></dt>
<dd>see <a href="#def-informative"><dfn>normative</dfn></a></dd>
<dt class="glossary"><a name="def-input-configuration"
id="def-input-configuration"><dfn>input configuration</dfn></a></dt>
<dd class="glossary">The set of bindings
between user agent functionalities and <a class="dfn-instance"
href="#def-user-interface" title="definition: User interface">user
interface</a> input mechanisms (e.g. menus, buttons, keyboard keys,
and voice commands). The default input configuration is the set of
bindings the user finds after installation of the software. Input
configurations may be affected by author-specified bindings (e.g.
through the <code>accesskey</code> attribute of HTML 4 <cite><a
href="#ref-HTML4"
title="Link to reference HTML4">[HTML4]</a></cite>).</dd>
<dt><dfn>input focus</dfn></dt>
<dd>see <a href="#def-input-focus"><dfn>focus</dfn></a></dd>
<dt class="glossary"> </dt>
<dt class="glossary"><a name="k" id="k"></a><a
name="def-keyboard-command"
id="def-keyboard-command"><dfn>keyboard command</dfn></a> (<a
name="def-keyboard-binding"
id="def-keyboard-binding"><dfn>keyboard binding</dfn></a>,<a
name="def-keyboard-shortcut"
id="def-keyboard-shortcut"><dfn>keyboard shortcuts</dfn></a> or <a
name="def-accelerator-key"
id="def-accelerator-key"><dfn>accelerator keys</dfn></a>)</dt>
<dd>Commands tied to particular UI controls or application functions, allowing the user to navigate-to or activate them without traversing any intervening controls (e.g. "ctrl"+"S" to save a document). It is sometimes useful to distinguish keyboard commands that are associated with controls that are rendered in the current context (e.g. "alt"+"D" to move focus to the address bar) from those that may be able to activate program functionality that is not associated with any currently rendered controls (e.g. "F1" to open the Help system). Keyboard commands help users accelerate their selections. </dd>
<dt><dfn>keyboard focus</dfn></dt>
<dd>see <a href="#def-keyboard-focus"><dfn>focus</dfn></a></dd>
<dt class="glossary"><a name="n" id="n"></a><a name="def-natural-language"
id="def-natural-language"><dfn>natural language</dfn></a></dt>
<dd class="glossary">Natural language is spoken, written, or signed human
language such as French, Japanese, and American Sign Language. On the
Web, the natural language of <a class="dfn-instance"
href="#def-content" title="definition: Content">content</a> may be
specified by markup or HTTP headers. Some examples include the <a
href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/dirlang.html#adef-lang"><code>lang</code>
attribute in <acronym>HTML</acronym> 4</a> (<cite><a href="#ref-HTML4"
title="Link to reference HTML4">[HTML4]</a></cite> section 8.1), the <a
href="http://www.w3.org/TR/1998/REC-xml-19980210#sec-lang-tag"><code>xml:lang</code>
attribute in <acronym>XML</acronym> 1.0</a> (<cite><a href="#ref-XML"
title="Link to reference XML">[XML]</a></cite>, section 2.12), the <a
href="http://www.w3.org/TR/1999/REC-html401-19991224/struct/links.html#adef-hreflang"><code>hreflang</code>
attribute</a> for links in <acronym>HTML</acronym> 4 (<cite><a
href="#ref-HTML4" title="Link to reference HTML4">[HTML4]</a></cite>,
section 12.1.5), the HTTP Content-Language header (<cite><a
href="#ref-RFC2616"
title="Link to reference RFC2616">[RFC2616]</a></cite>, section 14.12)
and the Accept-Language request header (<cite><a href="#ref-RFC2616"
title="Link to reference RFC2616">[RFC2616]</a></cite>, section 14.4).
See also the definition of <a class="dfn-instance" href="#def-script"
title="definition: Script">script</a>.</dd>
<dt><dfn>non-text content (non-text element, non-text equivalent)</dfn></dt>
<dd>see <a href="#def-text"><dfn>text</dfn></a></dd>
<dt class="glossary"><a name="def-normative"
id="def-normative"><dfn>normative</dfn></a>, <a name="def-informative"
id="def-informative"><dfn>informative (non-normative)</dfn></a> <span
class="glossary-adapted">[<a
href="http://www.w3.org/TR/WCAG20/#glossary">WCAG 2.0</a>, ATAG
2.0]</span></dt>
<dd class="glossary">What is identified as "normative" is required for <a
href="#conformance">conformance</a> (noting that one may conform in a
variety of well-defined ways to UAAG 2.0). What is identified as
"informative" (or, "non-normative") is never required for
conformance.</dd>
<dt class="glossary"><a name="def-alert"
id="def-alert"><dfn>notify</dfn></a></dt>
<dd class="glossary">To make the user aware of events or status changes. Notifications can occur within the user agent user interface (e.g. a status bar) or within the content display. Notifications may be passive and not require user acknowledgment, or they may be presented in the form of a prompt requesting a user response (e.g. a confirmation dialog).</dd>
<dt class="glossary"><a name="o" id="o"></a><a
name="def-operating-environment"
id="def-operating-environment"><dfn>operating environment</dfn></a></dt>
<dd class="glossary">The term "operating environment" refers to the
environment that governs the user agent's operation, whether it is an
operating system or a programming language environment such as
Java.</dd>
<dt class="glossary"><a name="def-override"
id="def-override"><dfn>override</dfn></a></dt>
<dd class="glossary">In UAAG 2.0, the term "override" means that one
configuration or behavior preference prevails over another. Generally,
the requirements of UAAG 2.0 involve user preferences prevailing
over author preferences and user agent default settings and behaviors.
Preferences may be multi-valued in general (e.g. the user prefers blue
over red or yellow), and include the special case of two values (e.g.
turn on or off blinking text content).</dd>
<dt class="glossary"><a name="p" id="p"></a><a name="def-placeholder"
id="def-placeholder"><dfn>placeholder</dfn></a></dt>
<dd class="glossary">A placeholder is content generated by the user agent
to replace author-supplied content. A placeholder may be generated as
the result of a user preference (e.g. to not render images) or as <a
class="dfn-instance" href="#def-repair-content"
title="definition: Repair content">repair content</a> (e.g. when an
image cannot be found). A placeholder can be any type of content,
including text, images, and audio cues. A placeholder should identify
the technology of the replaced object.
Placeholders appear in the alternative content stack. </dd>
<dt class="glossary"><a name="def-access-platform-arch"
id="def-access-platform-arch"><dfn>platform accessibility
architecture</dfn></a></dt>
<dd>A programmatic interface that is engineered to enhance
communication between mainstream software applications and assistive
technologies (e.g. MSAA, UI Automation, and IAccessible2 for Windows applications, AXAPI for MacOSX applications, Gnome Accessibility Toolkit API for Gnome applications, Java Access for Java applications). On some platforms it may be conventional to enhance
communication further via implementing a <a class="dfn-instance"
href="#def-dom" title="definition: Document Object Model">DOM</a>.</dd>
<dt class="glossary"><a name="def-plug-in"
id="def-plug-in"><dfn>plug-in</dfn></a> <span
class="glossary-adapted">[ATAG 2.0]</span></dt>
<dd class="glossary">A plug-in is a program that runs as part of the user
agent and that is <em>not</em> part of <a class="dfn-instance"
href="#def-content" title="definition: Content">content</a>. Users
generally choose to include or exclude plug-ins from their user
agents.</dd>
<dt class="glossary"><a name="def-point-of-regard"
id="def-point-of-regard"><dfn>point of regard</dfn></a></dt>
<dd class="glossary">The point of regard is the position in <a
class="dfn-instance" href="#def-rendered-content"
title="definition: Rendered content">rendered content</a> that the user
is presumed to be viewing. The dimensions of the point of regard may
vary. For example, it may be a point (e.g. a moment during an audio
rendering or a cursor position in a graphical rendering), or a range of
text (e.g. focused text), or a two-dimensional area (e.g. content
rendered through a two-dimensional graphical viewport). The point of
regard is almost always within the viewport, but it may exceed the
spatial or temporal <a href="#viewport-dimension">dimensions</a> of the
viewport (see the definition of <a class="dfn-instance"
href="#def-rendered-content"
title="definition: Rendered content">rendered content</a> for more
information about viewport dimensions). The point of regard may also
refer to a particular moment in time for content that changes over time
(e.g. an audio-only
presentation). User agents may determine the point of regard in a
number of ways, including based on viewport position in content, <a
class="dfn-instance" href="#def-content-focus"
title="definition: content focus">keyboard focus</a>, and <a
class="dfn-instance" href="#def-selection"
title="definition: Selection">selection</a>. The stability of the point
of regard is addressed by <span class="editor-notes">[@@ Editors' Note: Need reference here@@].</span></dd>
<dt><dfn>pointer</dfn></dt>
<dd>see <a href="#def-pointer"><dfn>focus</dfn></a></dd>
<dt><dfn>pointing device focus</dfn></dt>
<dd>see <a href="#def-pointing-device-focus"><dfn>focus</dfn></a></dd>
<dt class="glossary"><a name="def-profile"
id="def-profile"><dfn>profile</dfn></a></dt>
<dd class="glossary">A profile is a named and persistent representation
of user preferences that may be used to configure a user agent.
Preferences include input configurations, style preferences, and
natural language preferences. In <a class="dfn-instance"
href="#def-operating-environment"
title="definition: Operating environment">operating environments</a>
with distinct user accounts, profiles enable users to reconfigure
software quickly when they log on. Users may share their profiles with
one another.Platform-independent profiles are useful for those who use the same user agent on different devices. </dd>
<dt class="glossary"><a name="def-prompt"
id="def-prompt"><dfn>prompt</dfn></a> <span class="glossary-adapted">[ATAG
2.0]</span></dt>
<dd>Any user-agent-initiated request for a decision or piece of
information from a user.</dd>
<dt class="glossary"><a name="def-Properties-and-Values"
id="def-Properties-and-Values"><dfn>properties, values, and
defaults</dfn></a></dt>
<dd class="glossary">A user agent renders a document by applying
formatting algorithms and style information to the document's elements.
Formatting depends on a number of factors, including where the document
is rendered (e.g. on screen, on paper, through loudspeakers, on a braille
display, on a mobile device). Style information (e.g. fonts, colors,
synthesized speech prosody) may come from the elements themselves
(e.g. certain font and phrase elements in HTML), from style sheets, or
from user agent settings. For the purposes of these guidelines, each
formatting or style option is governed by a property and each property
may take one value from a set of legal values. Generally in UAAG 2.0, the term "<a
href="http://www.w3.org/TR/1998/REC-CSS2-19980512/conform.html">property</a>"
has the meaning defined in CSS 2 (<cite><a href="#ref-CSS2"
title="Link to reference CSS2">[CSS2]</a></cite>, section 3). A
reference to "styles" in UAAG 2.0 means a set of style-related
properties. The value given to a property by a user agent at
installation is the property's <a name="default-value"
id="default-value">default value</a>.</dd>
<dt class="glossary"><a name="r" id="r"></a><a name="def-recognize"
id="def-recognize"><dfn>recognize</dfn></a></dt>
<dd class="glossary">Authors encode information in many ways, including
in markup languages, style sheet languages, scripting languages, and
protocols. When the information is encoded in a manner that allows the
user agent to process it with certainty, the user agent can "recognize"
the information. For instance, HTML allows authors to specify a heading
with the <code>H1</code> element, so a user agent that implements HTML
can recognize that content as a heading. If the author creates a
heading using a visual effect alone (e.g. just by increasing the font
size), then the author has encoded the heading in a manner that does
not allow the user agent to recognize it as a heading. Some requirements of UAAG 2.0 depend on content roles, content
relationships, timing relationships, and other information supplied by
the author. These requirements only apply when the author has encoded
that information in a manner that the user agent can recognize. See the
section on <a href="#conformance">conformance</a> for more information
about applicability. User agents will rely heavily on information that the
author has encoded in a markup language or style sheet language. Behaviors, style, meaning encoded in a <a
class="dfn-instance" href="#def-script"
title="definition: Script">script</a>, and markup in an unfamiliar XML
namespace may not be recognized by the user agent as easily or at all. </dd>
<dt class="glossary"><a name="def-rendered-content"
id="def-rendered-content"><dfn>rendered content</dfn></a>, <a
name="def-rendered-text" id="def-rendered-text"><dfn>rendered
text</dfn></a></dt>
<dd class="glossary">Rendered content is the part of <a
class="dfn-instance" href="#def-content"
title="definition: Content">content</a> that the user agent makes
available to the user's senses of sight and hearing (and only those
senses for the purposes of UAAG 2.0). Any content that causes an
effect that may be perceived through these senses constitutes rendered
content. This includes text characters, images, style sheets, scripts,
and any other content that, once processed, may be perceived
through sight and hearing.</dd>
<dd class="glossary">The term "rendered text" refers to <a
class="dfn-instance" href="#def-text" title="definition: Text">text</a>
content that is rendered in a way that communicates information about
the characters themselves, whether visually or as synthesized
speech.</dd>
<dd class="glossary">In the context of UAAG 2.0, <a
name="def-invisible-content" id="def-invisible-content"><dfn>invisible
content</dfn></a> is content that is not rendered but that may
influence the graphical rendering (i.e. layout) of other content.
Similarly, <a name="def-silent-content"
id="def-silent-content"><dfn>silent content</dfn></a> is content that
is not rendered but that may influence the audio rendering of other
content. Neither invisible nor silent content is considered rendered
content.</dd>
<dt class="glossary"><a name="def-repair-content"
id="def-repair-content"><dfn>repair content</dfn></a>, <a
name="def-repair-text" id="def-repair-text"><dfn>repair text</dfn></a></dt>
<dd class="glossary">Content generated by the user agent to correct an error
condition. "Repair text" refers to the <a class="dfn-instance"
href="#def-text" title="definition: Text">text</a> portion of repair
content. Error conditions that may lead to the generation of
repair content include:
<ul>
<li>Erroneous or incomplete content (e.g. ill-formed markup, invalid
markup, or missing <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>
that is required by format specification);</li>
<li>Missing resources for handling or rendering content (e.g. the
user agent lacks a font family to display some characters, or the
user agent does not implement a particular scripting language).</li>
</ul>
<p>UAAG 2.0 does not require user agents to include repair content
in the <a class="dfn-instance" href="#def-document-object"
title="definition: Document object">document object</a>. Repair content
inserted in the document object should conform to the Web Content
Accessibility Guidelines 1.0 <cite><a href="#ref-WCAG10"
title="Link to reference WCAG10">[WCAG10]</a></cite>. For more
information about repair techniques for Web content and software, refer
to "Techniques for Authoring Tool Accessibility Guidelines 1.0"
<cite><a href="#ref-ATAG10-TECHS"
title="Link to reference ATAG10-TECHS">[ATAG10-TECHS]</a></cite>.</p>
</dd>
<dt class="glossary"><a name="s" id="s"></a><a name="def-script"
id="def-script"><dfn>script</dfn></a></dt>
<dd class="glossary">In UAAG 2.0, the term "script" almost always
refers to a scripting (programming) language used to create dynamic Web
content. However, in guidelines referring to the written (natural)
language of content, the term "script" is used as in Unicode <cite><a
href="#ref-UNICODE"
title="Link to reference UNICODE">[UNICODE]</a></cite> to mean "A
collection of symbols used to represent textual information in one or
more writing systems."</dd>
<dd class="glossary">Information encoded in (programming) scripts may be
difficult for a user agent to <a class="dfn-instance"
href="#def-recognize" title="definition: Recognize">recognize</a>. For
instance, a user agent is not expected to recognize that, when
executed, a script will calculate a factorial. The user agent will be
able to recognize some information in a script by virtue of
implementing the scripting language or a known program library (e.g.
the user agent is expected to recognize when a script will open a
viewport or retrieve a resource from the Web).</dd>
<dt class="glossary"><a name="def-selection-focus"
id="def-selection-focus"><dfn>selection</dfn></a>, <a
name="def-current-selection" id="def-current-selection"><dfn>current
selection</dfn></a></dt>
<dd>see <a href="#def-selection"><dfn>focus</dfn></a></dd>
<dt class="glossary"><a name="def-serial-access"
id="def-serial-access"><dfn>serial access</dfn></a>, <a
name="def-sequential-navigation"
id="def-sequential-navigation"><dfn>sequential navigation</dfn></a></dt>
<dd class="glossary"><a href="#viewport-dimension">One-dimensional</a> access to
rendered content. Some examples of serial access include listening to
an audio stream or watching a video (both of which involve one temporal
dimension), or reading a series of lines of braille one line at a time
(one spatial dimension). Many users with blindness have serial access
to content rendered as audio, synthesized speech, or lines of braille.
<p>The expression "sequential navigation" refers to navigation through
an ordered set of items (e.g. the <a class="dfn-instance"
href="#def-enabled-element" title="definition: Enabled element">enabled
elements</a> in a document, a sequence of lines or pages, or a sequence
of menu options). Sequential navigation implies that the user cannot
skip directly from one member of the set to another, in contrast to
direct or structured navigation. Users with blindness or some users
with a physical disability may navigate content sequentially (e.g. by
navigating through links, one by one, in a graphical viewport with or
without the aid of an assistive technology). Sequential navigation is
important to users who cannot scan rendered content visually for
context and also benefits users unfamiliar with content. The increments
of sequential navigation may be determined by a number of factors,
including element type (e.g. links only), content structure (e.g.
navigation from heading to heading), and the current navigation context
(e.g. having navigated to a table, allow navigation among the table
cells).</p>
<p>Users with serial access to content or who navigate sequentially may
require more time to access content than users who use direct or
structured navigation.</p>
</dd>
<dt class="glossary"><a name="def-support"
id="def-support"><dfn>support</dfn></a>, <a name="def-implement"
id="def-implement"><dfn>implement</dfn></a>, <a name="def-conform"
id="def-conform"><dfn>conform</dfn></a></dt>
<dd class="GLOSSARY">Support, implement,
and conform all refer to what a developer has designed a user agent
to do, but they represent different degrees of specificity. A user
agent "supports" general classes of objects, such as "images" or
"Japanese." A user agent "implements" a specification (e.g. the PNG
and SVG image format specifications or a particular scripting
language), or an <a class="dfn-instance" href="#def-api"
title="definition: Application Programming Interface (API)">API</a>
(e.g. the DOM API) when it has been programmed to follow all or part
of a specification. A user agent "conforms to" a specification when it
implements the specification <em>and</em> satisfies its conformance
criteria.</dd>
<dt class="glossary"><a name="def-synchronize"
id="def-synchronize"><dfn>synchronize</dfn></a></dt>
<dd class="GLOSSARY">The act
of time-coordinating two or more presentation components (e.g. a <a
class="dfn-instance" href="#def-visual-track"
title="definition: Visual track">visual track</a> with captions, or
several tracks in a multimedia presentation). For Web content
developers, the requirement to synchronize means to provide the data
that will permit sensible time-coordinated rendering by a user agent.
For example, Web content developers can ensure that the segments of
caption text are neither too long nor too short, and that they map to
segments of the visual track that are appropriate in length. For user
agent developers, the requirement to synchronize means to present the
content in a sensible time-coordinated fashion under a wide range of
circumstances including technology constraints (e.g. small text-only
displays), user limitations (e.g. slow reading speeds, large font sizes,
high need for review or repeat functions), and content that is
sub-optimal in terms of accessibility.</dd>
<dt><a name="t" id="t"></a><a id="def-Web-Content-Technology"
name="def-Web-Content-Technology"><dfn>technology (web content technology)</dfn></a> <span class="glossary-adapted">[<a
href="http://www.w3.org/TR/WCAG20/#glossary">WCAG 2.0</a>, ATAG
2.0]</span></dt>
<dd>A mechanism for encoding instructions to be rendered, played or
executed by <a href="#def-user-agent">user agents</a>. Web Content
technologies may include markup languages, data formats, or programming
languages that <a href="#def-author">authors</a> may use alone or in
combination to create end-user experiences that range from static Web
pages to multimedia presentations to dynamic Web applications. Some
common examples of Web content technologies include HTML, CSS, SVG,
PNG, PDF, Flash, and JavaScript.</dd>
<dt><a name="def-text" id="def-text"><dfn>text</dfn></a> (<dfn>text content</dfn>, <dfn>non-text
content</dfn>,
<dfn>text element</dfn>, <dfn>non-text
element</dfn>, <dfn>text
equivalent</dfn>, <dfn>non-text equivalent </dfn>)</dt>
<dd class="glossary">Text used by itself
refers to a sequence of characters from a markup language's <a
class="dfn-instance" href="#def-doc-char-set"
title="definition: Document character set">document character set</a>.
Refer to the "Character Model for the World Wide Web" <cite><a
href="#ref-CHARMOD"
title="Link to reference CHARMOD">[CHARMOD]</a></cite> for more
information about text and characters. <strong>Note:</strong> UAAG 2.0 makes use of other terms that include the word "text" that
have highly specialized meanings: <a class="dfn-instance"
href="#def-collated-text-transcript"
title="definition: Collated text transcript">collated text
transcript</a>, <a class="dfn-instance" href="#def-non-text-content"
title="definition: non-text content">non-text content</a>, <a
class="dfn-instance" href="#def-text-content"
title="definition: Text content">text content</a>, <a
class="dfn-instance" href="#def-non-text-element"
title="definition: non-text element">non-text element</a>, <a
class="dfn-instance" href="#def-text-element"
title="definition: text element">text element</a>, <a
class="dfn-instance" href="#def-text-eq"
title="definition: text equivalent">text equivalent</a>, and <a
class="dfn-instance" href="#def-text-transcript"
title="definition: Text transcript">text transcript</a>.
<p>A<a name="def-text-element"
id="def-text-element"><dfn>text element</dfn></a> adds <a
class="dfn-instance" href="#def-text" title="definition: Text">text
characters</a> to either <a class="dfn-instance" href="#def-content"
title="definition: Content">content</a> or the <a class="dfn-instance"
href="#def-user-interface" title="definition: User interface">user
interface</a>. Both in the Web Content Accessibility Guidelines 2.0 <cite><a href="#ref-WCAG20"
title="Link to reference WCAG20">[WCAG20]</a></cite> and in UAAG 2.0, text elements are presumed to produce text that can be
understood when rendered visually, as synthesized speech, or as
Braille. Such text elements benefit at least these three groups of
users: </p>
<ol>
<li>visually-displayed text benefits users who are deaf and adept in
reading visually-displayed text;</li>
<li>synthesized speech benefits users who are blind and adept in use
of synthesized speech;</li>
<li>braille benefits users who are blind, and possibly deaf-blind,
and adept at reading braille.</li>
</ol>
<p>A text element may consist of both text and non-text data. For
instance, a text element may contain markup for style (e.g. font size
or color), structure (e.g. heading levels), and other semantics. The
essential function of the text element should be retained even if style
information happens to be lost in rendering. A user agent may have to process a text element in order to have
access to the text characters. For instance, a text element may consist
of markup, it may be encrypted or compressed, or it may include
embedded text in a binary format (e.g. <acronym>JPEG</acronym>).</p>
<p><a name="def-text-content"
id="def-text-content"><dfn>Text content</dfn></a> is content that is composed of one or more text
elements. A <a name="def-text-eq" id="def-text-eq"><dfn>text
equivalent</dfn></a> (whether in content or the user
interface) is an <a class="dfn-instance" href="#def-equivalent"
title="definition: Equivalent (for content)">equivalent</a> composed of
one or more text elements. Authors generally provide text equivalents
for content by using the <a class="dfn-instance"
href="#def-conditional-content"
title="definition: Conditional content">alternative content</a>
mechanisms of a specification.</p>
<p>A <a
name="def-non-text-element" id="def-non-text-element"><dfn>non-text
element</dfn></a> is an element (in content or the user
interface) that does not have the qualities of a text element.
<a
name="def-non-text-content" id="def-non-text-content"><dfn>Non-text
content</dfn></a> is composed of one or more non-text elements. A
<a name="def-non-text-eq"
id="def-non-text-eq"><dfn>non-text equivalent</dfn></a> (whether in content or the user interface) is an
<a class="dfn-instance" href="#def-equivalent"
title="definition: Equivalent (for content)">equivalent</a> composed of
one or more non-text elements.</p>
</dd>
<dt class="glossary"><a name="def-text-decoration"
id="def-text-decoration"><dfn>text decoration</dfn></a></dt>
<dd class="glossary">Any
stylistic effect that the user agent may apply to visually <a
class="dfn-instance" href="#def-rendered-text"
title="definition: rendered text">rendered text</a> that does not
affect the layout of the document (i.e. does not require reformatting
when applied or removed). Text decoration mechanisms include underline,
overline, and strike-through.</dd>
<dt class="glossary"><a name="def-text-format"
id="def-text-format"><dfn>text format</dfn></a></dt>
<dd class="glossary">Any media object given an Internet media type of
"text" (e.g. "text/plain", "text/html", or "text/*") as defined in RFC
2046 <cite class="normref"><a href="#ref-RFC2046"
title="Link to reference RFC2046">[RFC2046]</a></cite>, section 4.1, or
any media object identified by Internet media type to be an XML
document (as defined in <cite class="normref"><a href="#ref-XML"
title="Link to reference XML">[XML]</a></cite>, section 2) or SGML
application. Refer, for example, to Internet media types defined in
"XML Media Types" <cite><a href="#ref-RFC3023"
title="Link to reference RFC3023">[RFC3023]</a></cite>.</dd>
<dt class="glossary"><a name="def-text-transcript"
id="def-text-transcript"><dfn>text transcript</dfn></a></dt>
<dd class="glossary">A text equivalent of audio
information (e.g. an audio-only presentation
or the <a class="dfn-instance" href="#def-audio-track"
title="definition: Audio track">audio track</a> of a movie or other
animation). A text transcript provides text for both spoken words and non-spoken
sounds such as sound effects. Text transcripts make audio information
accessible to people who have hearing disabilities and to people who
cannot play the audio. Text transcripts are usually created by hand but
may be generated on the fly (e.g. by voice-to-text converters). See
also the definitions of <a class="dfn-instance" href="#def-captions"
title="definition: Captions">captions</a> and <a class="dfn-instance"
href="#def-collated-text-transcript"
title="definition: Collated text transcript">collated text
transcripts</a>.</dd>
<dt class="glossary"><a name="def-audio-track"
id="def-audio-track"><dfn>track</dfn></a> (<dfn>audio track</dfn> or <a href="#def-visual-track">
visual track</a>)</dt>
<dd class="glossary"><a href="#def-content"
title="definition: Content">Content</a> rendered as sound through an
audio <a class="dfn-instance" href="#def-viewport"
title="definition: viewport">viewport</a>. The audio track may be all
or part of the audio portion presentation (e.g. each instrument may
have a track, or each stereo channel may have a track). Also see definition of <a href="#def-visual-track">visual track</a></dd>
<dt class="glossary"><a name="u" id="u"></a><a name="def-user-agent"
id="def-user-agent"><dfn>user agent</dfn></a></dt>
<dd class="GLOSSARY">A user agent is any software that retrieves, renders
and facilitates end user interaction with Web content. </dd>
<dt class="glossary"><a name="def-default-styles"
id="def-default-styles"><dfn>user agent default styles</dfn></a></dt>
<dd class="glossary">User agent default styles are <a
class="dfn-instance" href="#def-Properties-and-Values"
title="definition: Properties, values, and defaults">style property
values</a> applied in the absence of any author or user styles. Some
markup languages specify a default rendering for content in that markup
language; others do not. For example, <acronym>XML</acronym> 1.0
<cite><a href="#ref-XML" title="Link to reference XML">[XML]</a></cite>
does not specify default styles for XML documents.
<acronym>HTML</acronym> 4 <cite><a href="#ref-HTML4"
title="Link to reference HTML4">[HTML4]</a></cite> does not specify
default styles for HTML documents, but the CSS 2 <cite><a
href="#ref-CSS2" title="Link to reference CSS2">[CSS2]</a></cite>
specification suggests a <a
href="http://www.w3.org/TR/1998/REC-CSS2-19980512/sample.html">sample
default style sheet for HTML 4</a> based on current practice.</dd>
<dt class="glossary"><a name="def-user-interface"
id="def-user-interface"><dfn>user interface</dfn></a>, <a
name="def-ui-control" id="def-ui-control"><dfn>user interface
control</dfn></a></dt>
<dd class="glossary">For the purposes of UAAG 2.0, user interface
includes both:
<ol>
<li>the <a name="def-ua-ui" id="def-ua-ui"><dfn>user agent user
interface</dfn></a>, i.e. the controls (e.g. menus, buttons,
prompts, and other components for input and output) and mechanisms
(e.g. selection and focus) provided by the user agent ("out of the
box") that are not created by <a class="dfn-instance"
href="#def-content" title="definition: Content">content</a>.</li>
<li>the "content user interface," i.e. the <a class="dfn-instance"
href="#def-enabled-element"
title="definition: Enabled element">enabled elements</a> that are
part of content, such as form controls, links, and applets.</li>
</ol>
The document distinguishes them only where required for clarity. For
more information, see the section on requirements for content, for user
agent features, or both @@.
<p>The term "user interface control" refers to a component of the user
agent user interface or the content user interface, distinguished where
necessary.</p>
</dd>
<dt class="glossary"><a name="def-user-styles"
id="def-user-styles"><dfn>user styles</dfn></a></dt>
<dd class="glossary">User styles are <a class="dfn-instance"
href="#def-Properties-and-Values"
title="definition: Properties, values, and defaults">style property
values</a> that come from user interface settings, user style sheets,
or other user interactions.</dd>
<dt><a name="v" id="v"></a><dfn>values</dfn></dt>
<dd>see <a href="#def-Properties-and-Values"><dfn>properties</dfn></a></dd>
<dt class="glossary"><a name="def-view"
id="def-view"><dfn>view</dfn></a>, <a name="def-viewport"
id="def-viewport"><dfn>viewport</dfn></a></dt>
<dd class="glossary">The user agent <a class="dfn-instance"
href="#def-rendered-content"
title="definition: Rendered content">renders content</a> through one or
more viewports. Viewports include windows, frames, pieces of paper,
loudspeakers, and virtual magnifying glasses. A viewport may contain
another viewport (e.g. nested frames). <a class="dfn-instance"
href="#def-ui-control" title="definition: user interface control">User
agent user interface controls</a> such as prompts, menus, and alerts
are not viewports.
<p>Graphical and tactile viewports have two spatial <a
name="viewport-dimension"
id="viewport-dimension"><dfn>dimensions</dfn></a>. A viewport may also
have temporal dimensions, for instance when audio, speech, animations,
and movies are rendered. When the dimensions (spatial or temporal) of
rendered content exceed the dimensions of the viewport, the user agent
provides mechanisms such as scroll bars and advance and rewind controls
so that the user can access the rendered content "outside" the
viewport. Examples include: when the user can only view a portion of a
large document through a small graphical viewport, or when audio
content has already been played.</p>
<p>When several viewports coexist, only one has the <a
class="dfn-instance" href="#def-current-focus"
title="definition: current focus">current focus</a> at a given moment.
This viewport is <a class="dfn-instance" href="#def-highlight"
title="definition: Highlight">highlighted</a> to make it stand out.</p>
<p>User agents may render the same content in a variety of ways; each
rendering is called a <em>view</em>. For instance, a user agent may
allow users to view an entire document or just a list of the document's
headers. These are two different views of the document.<br />
<br />
<dfn><a name="def-viewport-toplevel"
id="def-viewport-toplevel"></a>top-level viewports</dfn> are
viewports that are not contained within other user agent viewports.</p>
</dd>
<dt class="glossary"><a name="def-visual-only-presentation"
id="def-visual-only-presentation"><dfn>visual-only
presentation</dfn></a></dt>
<dd class="glossary">A visual-only presentation is content consisting
exclusively of one or more <a class="dfn-instance"
href="#def-visual-track" title="definition: Visual track">visual
tracks</a> presented concurrently or in series. A silent movie is an
example of a visual-only presentation.</dd>
<dt class="glossary"><a name="def-visual-track"
id="def-visual-track"><dfn>visual track</dfn></a></dt>
<dd class="glossary">A visual object is content rendered through a
graphical <a class="dfn-instance" href="#def-viewport"
title="definition: viewport">viewport</a>. Visual objects include
graphics, text, and visual portions of movies and other animations. A
visual track is a visual object that is intended as a whole or partial
presentation. A visual track does not necessarily correspond to a
single physical object or software object.</dd>
<dt class="glossary"><a name="def-voice-browser"
id="def-voice-browser"><dfn>voice browser</dfn></a></dt>
<dd class="glossary">From "Introduction and Overview of W3C Speech
Interface Framework" <cite><a href="#ref-VOICEBROWSER"
title="Link to reference VOICEBROWSER">[VOICEBROWSER]</a></cite>: "A
voice browser is a device (hardware and software) that interprets voice
markup languages to generate voice output, interpret voice input, and
possibly accept and produce other modalities of input and output."</dd>
<dt class="glossary"><a name="w" id="w"></a><a name="def-web-resource"
id="def-web-resource"><dfn>web resource</dfn></a></dt>
<dd>Anything that can be identified by a Uniform Resource Identifier
(<acronym>URI</acronym>).</dd>
</dl>
<hr />
<div id="sect-this-doc-ref">
<h2><a name="ref-this-doc" id="ref-this-doc"></a>Appendix B: How to refer to
UAAG 2.0 from other documents</h2>
<p>This section is <a href="#def-informative" title="definition: informative" class="termdef">informative</a>. </p>
<p>There are two recommended ways to refer to the "User Agent Accessibility
Guidelines 2.0" (and to W3C documents in general):</p>
<ol>
<li>References to a specific version of "User Agent Accessibility
Guidelines 2.0." For example, use the "this version" <acronym>URI</acronym> to
refer to the current document:<br />
<a href="http://www.w3.org/TR/2010/WD-UAAG20-20100617/">http://www.w3.org/TR/2010/WD-UAAG20-20100617/</a></li>
<li>References to the latest version of "User Agent Accessibility
Guidelines 2.0." Use the "latest version" URI to refer to
the most recently published document in the series: <br />
<a href="http://www.w3.org/TR/UAAG20/">http://www.w3.org/TR/UAAG20/</a>.</li>
</ol>
<p>In almost all cases, references (either by name or by link) should be to
a specific version of the document. W3C will make every effort to make UAAG 2.0 indefinitely available at its original address in its original form.
The top of UAAG 2.0 includes the relevant catalog metadata for specific
references (including title, publication date, "this version" <acronym>URI</acronym>,
editors' names, and copyright information).</p>
<div id="example">
<p>An XHTML 1.0 paragraph including a reference to this specific document
might be written: </p>
<blockquote>
<p><code><p><br />
<cite><a href="http://www.w3.org/TR/2010/WD-UAAG20-20100617/"><br />
"User Agent Accessibility Guidelines 2.0,"</a></cite><br />
J. Allan, K. Ford, J. Spellman, eds.,<br />
W3C Recommendation, http://www.w3.org/TR/ATAG20/.<br />
The <a href="http://www.w3.org/TR/ATAG20/">latest version</a> of this document is available at http://www.w3.org/TR/ATAG20/.</p> </code></p>
</blockquote>
</div> <!-- example -->
<p>For very general references to this document (where stability of content
and anchors is not required), it may be appropriate to refer to the latest
version of this document. Other sections of this document explain how to build a <a href="#conformance">conformance
claim</a>.</p>
<hr />
</div> <!-- sect-this-doc-ref -->
<h2><a name="references" id="references"></a>Appendix C: References</h2>
<p>This section is <a href="#def-informative">informative</a>.</p>
<p>For the <strong>latest version</strong> of any <acronym
title="the World Wide Web Consortium">W3C</acronym> specification please
consult the list of <a href="http://www.w3.org/TR/"><acronym
title="the World Wide Web Consortium">W3C</acronym> Technical Reports</a> at
http://www.w3.org/TR/. Some documents listed below may have been superseded
since the publication of UAAG 2.0.</p>
<p><strong>Note:</strong> In UAAG 2.0, bracketed labels such as
"[WCAG20]" link to the corresponding entries in this section. These labels
are also identified as references through markup.</p>
<dl>
<dt><a name="ref-CSS1" id="ref-CSS1">[CSS1]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/1999/REC-CSS1-19990111">"Cascading Style
Sheets (CSS1) Level 1 Specification,"</a></cite> B. Bos, H. Wium Lie,
eds., 17 December 1996, revised 11 January 1999. This W3C
Recommendation is http://www.w3.org/TR/1999/REC-CSS1-19990111.</dd>
<dt><a name="ref-CSS2" id="ref-CSS2">[CSS2]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/1998/REC-CSS2-19980512/">"Cascading Style
Sheets, level 2 (CSS2) Specification,"</a></cite> B. Bos, H. Wium Lie,
C. Lilley, and I. Jacobs, eds., 12 May 1998. This W3C Recommendation is
http://www.w3.org/TR/1998/REC-CSS2-19980512/.</dd>
<dt><a name="ref-DOM2CORE" id="ref-DOM2CORE">[DOM2CORE]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113/">"Document
Object Model (DOM) Level 2 Core Specification,"</a></cite> A. Le Hors,
P. Le Hégaret, L. Wood, G. Nicol, J. Robie, M. Champion, S. Byrne,
eds., 13 November 2000. This W3C Recommendation is
http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113/.</dd>
<dt><a name="ref-DOM2STYLE" id="ref-DOM2STYLE">[DOM2STYLE]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2000/REC-DOM-Level-2-Style-20001113/">"Document
Object Model (DOM) Level 2 Style Specification,"</a></cite> V. Apparao,
P. Le Hégaret, C. Wilson, eds., 13 November 2000. This W3C
Recommendation is
http://www.w3.org/TR/2000/REC-DOM-Level-2-Style-20001113/.</dd>
<dt><a name="ref-INFOSET" id="ref-INFOSET">[INFOSET]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2001/REC-xml-infoset-20011024/">"XML
Information Set,"</a></cite> J. Cowan and R. Tobin, eds., 24 October
2001. This W3C Recommendation is
http://www.w3.org/TR/2001/REC-xml-infoset-20011024/.</dd>
<dt><a name="ref-RFC2046" id="ref-RFC2046">[RFC2046]</a></dt>
<dd><cite><a href="http://www.ietf.org/rfc/rfc2046.txt">"Multipurpose
Internet Mail Extensions (MIME) Part Two: Media Types,"</a></cite> N.
Freed, N. Borenstein, November 1996.</dd>
<dt><a name="ref-WCAG10" id="ref-WCAG10">[WCAG10]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/1999/WAI-WEBCONTENT-19990505/">"Web Content
Accessibility Guidelines 1.0,"</a></cite> W. Chisholm, G. Vanderheiden,
and I. Jacobs, eds., 5 May 1999. This W3C Recommendation is
http://www.w3.org/TR/1999/WAI-WEBCONTENT-19990505/.</dd>
<dt><a name="ref-XML" id="ref-XML">[XML]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/1998/REC-xml-19980210">"Extensible Markup
Language (XML) 1.0 (Second Edition),"</a></cite> T. Bray, J. Paoli,
C.M. Sperberg-McQueen, eds., 6 October 2000. This W3C Recommendation is
http://www.w3.org/TR/2000/REC-xml-20001006.</dd>
</dl>
<dl>
<dt><a name="ref-AT1998" id="ref-AT1998">[AT1998]</a></dt>
<dd>The <cite><a
href="http://www.section508.gov/508Awareness/html/at1998.html">Assistive Technology
Act of 1998</a></cite>.</dd>
<dt><a name="ref-ATAG10" id="ref-ATAG10">[ATAG10]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2000/REC-ATAG10-20000203/">"Authoring Tool
Accessibility Guidelines 1.0,"</a></cite> J. Treviranus, C.
McCathieNevile, I. Jacobs, and J. Richards, eds., 3 February 2000. This
W3C Recommendation is
http://www.w3.org/TR/2000/REC-ATAG10-20000203/.</dd>
<dt><a name="ref-ATAG10-TECHS" id="ref-ATAG10-TECHS">[ATAG10-TECHS]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2002/NOTE-ATAG10-TECHS-20021029/">"Techniques
for Authoring Tool Accessibility Guidelines 1.0,"</a></cite> J.
Treviranus, C. McCathieNevile, J. Richards, eds., 29 Oct 2002. This W3C
Note is http://www.w3.org/TR/2002/NOTE-ATAG10-TECHS-20021029/.</dd>
<dt><a name="ref-CHARMOD" id="ref-CHARMOD">[CHARMOD]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2002/WD-charmod-20020430/">"Character Model
for the World Wide Web,"</a></cite> M. Dürst and F. Yergeau, eds., 30
April 2002. This W3C Working Draft is
http://www.w3.org/TR/2002/WD-charmod-20020430/. The <a
href="http://www.w3.org/TR/charmod/">latest version</a> is available at
http://www.w3.org/TR/charmod/.</dd>
<dt><a name="ref-DOM2HTML" id="ref-DOM2HTML">[DOM2HTML]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2002/PR-DOM-Level-2-HTML-20021108/">"Document
Object Model (DOM) Level 2 HTML Specification,"</a></cite> J. Stenback,
P. Le Hégaret, A. Le Hors, eds., 8 November 2002. This W3C Proposed
Recommendation is
http://www.w3.org/TR/2002/PR-DOM-Level-2-HTML-20021108/. The <a
href="http://www.w3.org/TR/DOM-Level-2-HTML/">latest version</a> is
available at http://www.w3.org/TR/DOM-Level-2-HTML/.</dd>
<dt><a name="ref-HTML4" id="ref-HTML4">[HTML4]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/1999/REC-html401-19991224/">"HTML
4.01 Recommendation,"</a></cite> D. Raggett, A. Le Hors, and I. Jacobs,
eds., 24 December 1999. This W3C Recommendation is
http://www.w3.org/TR/1999/REC-html401-19991224/.</dd>
<dt><a name="ref-RFC2616" id="ref-RFC2616">[RFC2616]</a></dt>
<dd><cite><a href="http://www.ietf.org/rfc/rfc2616.txt">"Hypertext
Transfer Protocol — HTTP/1.1,"</a></cite> J. Gettys, J. Mogul, H.
Frystyk, L. Masinter, P. Leach, T. Berners-Lee, June 1999.</dd>
<dt><a name="ref-RFC3023" id="ref-RFC3023">[RFC3023]</a></dt>
<dd><cite><a href="http://www.ietf.org/rfc/rfc3023.txt">"XML Media
Types,"</a></cite> M. Murata, S. St. Laurent, D. Kohn, January
2001.</dd>
<dt><a name="ref-SMIL" id="ref-SMIL">[SMIL]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/1998/REC-smil-19980615/">"Synchronized
Multimedia Integration Language (SMIL) 1.0 Specification,"</a></cite>
P. Hoschka, ed., 15 June 1998. This W3C Recommendation is
http://www.w3.org/TR/1998/REC-smil-19980615/.</dd>
<dt><a name="ref-SMIL20" id="ref-SMIL20">[SMIL20]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2001/REC-smil20-20010807/">"Synchronized
Multimedia Integration Language (SMIL 2.0) Specification,"</a></cite>
J. Ayars, et al., eds., 7 August 2001. This W3C Recommendation is
http://www.w3.org/TR/2001/REC-smil20-20010807/.</dd>
<dt><a name="ref-SVG" id="ref-SVG">[SVG]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/2001/REC-SVG-20010904/">"Scalable
Vector Graphics (SVG) 1.0 Specification,"</a></cite> J. Ferraiolo, ed.,
4 September 2001. This W3C Recommendation is
http://www.w3.org/TR/2001/REC-SVG-20010904/.</dd>
<dt><a name="ref-UAAG10" id="ref-UAAG10"><strong>[UAAG10]</strong></a></dt>
<dd>"<a href="http://www.w3.org/TR/2002/REC-UAAG10-20021217/">User Agent
Accessibility Guidelines 1.0</a>," I. Jacobs, J. Gunderson, E. Hansen,
eds.17 December 2002. This W3C Recommendation is available at
http://www.w3.org/TR/2002/REC-UAAG10-20021217/. </dd>
<dt><a name="ref-UAAG10-CHECKLIST"
id="ref-UAAG10-CHECKLIST">[UAAG10-CHECKLIST]</a></dt>
<dd>An appendix to UAAG 2.0 lists all of the checkpoints, sorted by
priority. The checklist is available in either <a rel="Appendix"
title="Tabular form of AUGL Checklist"
href="http://www.w3.org/TR/2002/REC-UAAG10-20021217/uaag10-chktable">tabular
form</a> or <a rel="Appendix" title="List form of AUGL Checklist"
href="http://www.w3.org/TR/2002/REC-UAAG10-20021217/uaag10-chklist">list
form</a>.</dd>
<dt><a name="ref-UAAG10-ICONS" id="ref-UAAG10-ICONS">[UAAG10-ICONS]</a></dt>
<dd>Information about <a
href="http://www.w3.org/WAI/UAAG10-Conformance">UAAG 1.0 conformance
icons</a> and their usage is available at
http://www.w3.org/WAI/UAAG10-Conformance.</dd>
<dt><a name="ref-UAAG10-SUMMARY"
id="ref-UAAG10-SUMMARY">[UAAG10-SUMMARY]</a></dt>
<dd>An appendix to UAAG 2.0 provides a <a
href="http://www.w3.org/TR/2002/REC-UAAG10-20021217/uaag10-summary"
rel="Appendix">summary</a> of the goals and structure of User Agent
Accessibility Guidelines 1.0.</dd>
<dt><a name="ref-UAAG10-TECHS" id="ref-UAAG10-TECHS">[UAAG10-TECHS]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/UAAG10-TECHS/">"Techniques for
User Agent Accessibility Guidelines 1.0,"</a></cite> I. Jacobs, J.
Gunderson, E. Hansen, eds. The latest draft of the techniques document
is available at http://www.w3.org/TR/UAAG10-TECHS/.</dd>
<dt><a name="ref-UNICODE" id="ref-UNICODE">[UNICODE]</a></dt>
<dd><cite><a href="http://www.unicode.org/reports/tr28/">"The
Unicode Standard, Version 3.2."</a></cite> This technical report of the
<a href="http://www.unicode.org/">Unicode Consortium</a> is available
at http://www.unicode.org/reports/tr28/. This is a revision of
"The Unicode Standard, Version 3.0," The Unicode Consortium,
Addison-Wesley Developers Press, 2000. ISBN 0-201-61633-5. Refer also
to <a
href="http://www.unicode.org/standard/versions/">http://www.unicode.org/standard/versions/</a>.
For information about character encodings, refer
to <a href="http://www.unicode.org/reports/tr17/">Unicode
Technical Report #17 "Character Encoding Model"</a>.</dd>
<dt><a name="ref-VOICEBROWSER" id="ref-VOICEBROWSER">[VOICEBROWSER]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2000/WD-voice-intro-20001204/">"Introduction
and Overview of W3C Speech Interface Framework,"</a></cite> J. Larson,
4 December 2000. This W3C Working Draft is
http://www.w3.org/TR/2000/WD-voice-intro-20001204/. The <a
href="http://www.w3.org/TR/voice-intro/">latest version</a> is
available at http://www.w3.org/TR/voice-intro/. UAAG 2.0 includes
references to additional W3C specifications about voice browser
technology.</dd>
<dt><a name="ref-W3CPROCESS" id="ref-W3CPROCESS">[W3CPROCESS]</a></dt>
<dd><cite><a href="http://www.w3.org/Consortium/Process-20010719/">"World
Wide Web Consortium Process Document,"</a></cite> I. Jacobs ed. The 19
July 2001 version of the Process Document is
http://www.w3.org/Consortium/Process-20010719/. The <a
href="http://www.w3.org/Consortium/Process/">latest version</a> is
available at http://www.w3.org/Consortium/Process/.</dd>
<dt><a name="ref-WCAG20" id="ref-WCAG20">[WCAG20]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/WCAG20/">"Web Content Accessibility Guidelines (WCAG) 2.0"</a></cite> B. Caldwell, M. Cooper, L. Guarino Reid, G. Vanderheiden, eds., 8 December 2008. This W3C Recommendation is
http://www.w3.org/TR/2008/REC-WCAG20-20081211/. The <a
href="http://www.w3.org/TR/WCAG20/">latest version</a> is
available at http://www.w3.org/TR/WCAG20/. Additional
format-specific techniques documents are available from this Recommendation.</dd>
<dt><a name="ref-WCAG10-TECHS" id="ref-WCAG10-TECHS">[WCAG20-TECHS]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/WCAG10-TECHS/">"Techniques for
Web Content Accessibility Guidelines 2.0,"</a></cite> B. Caldwell, M. Cooper, L. Guarino Reid, G. Vanderheiden, eds., 8 December 2008. This W3C Note is
http://www.w3.org/TR/2010/NOTE-WCAG20-TECHS-20101014/. The <a
href="http://www.w3.org/TR/WCAG20-TECHS/">latest version</a> is
available at http://www.w3.org/TR/WCAG20-TECHS/. Additional
format-specific techniques documents are available from this Note.</dd>
<dt><a name="ref-WEBCHAR" id="ref-WEBCHAR">[WEBCHAR]</a></dt>
<dd><cite><a href="http://www.w3.org/1999/05/WCA-terms/01">"Web
Characterization Terminology and Definitions Sheet,"</a></cite> B.
Lavoie, H. F. Nielsen, eds., 24 May 1999. This is a W3C Working Draft
that defines some terms to establish a common understanding about key
Web concepts. This W3C Working Draft is
http://www.w3.org/1999/05/WCA-terms/01.</dd>
<dt><a name="ref-XAG10" id="ref-XAG10">[XAG10]</a></dt>
<dd><cite><a href="http://www.w3.org/TR/2002/WD-xag-20021003">"XML
Accessibility Guidelines 1.0,"</a></cite> D. Dardailler, S. Palmer, C.
McCathieNevile, eds., 3 October 2001. This W3C Working Draft is
http://www.w3.org/TR/2002/WD-xag-20021003. The <a
href="http://www.w3.org/TR/xag">latest version</a> is available at
http://www.w3.org/TR/xag.</dd>
<dt><a name="ref-XHTML10" id="ref-XHTML10">[XHTML10]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2000/REC-xhtml1-20000126/">"XHTML[tm] 1.0:
The Extensible HyperText Markup Language,"</a></cite> S. Pemberton, et
al., 26 January 2000. This W3C Recommendation is
http://www.w3.org/TR/2000/REC-xhtml1-20000126/.</dd>
<dt><a name="ref-XMLDSIG" id="ref-XMLDSIG">[XMLDSIG]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/">"XML-Signature
Syntax and Processing,"</a></cite> D. Eastlake, J. Reagle, D. Solo,
eds., 12 February 2002. This W3C Recommendation is
http://www.w3.org/TR/2002/REC-xmldsig-core-20020212/.</dd>
<dt><a name="ref-XMLENC" id="ref-XMLENC">[XMLENC]</a></dt>
<dd><cite><a
href="http://www.w3.org/TR/2002/REC-xmlenc-core-20021210/">"XML
Encryption Syntax and Processing,"</a></cite> D. Eastlake, J. Reagle,
eds., 10 December 2002. This W3C Recommendation is
http://www.w3.org/TR/2002/REC-xmlenc-core-20021210/.</dd>
</dl>
<hr />
<h2><a id="acknowledgments" name="acknowledgments"></a>Appendix D:
Acknowledgments</h2>
<h3><a name="active-participants" id="active-participants"></a>Participants
active in the UAWG prior publication:</h3>
<ul>
<li>Jim Allan (Co-Chair, Texas School for the Blind and Visually
Impaired)</li>
<li>Alan Cantor (Invited Expert)</li>
<li>Bim Egan (Royal National Institute of Blind People)</li>
<li>Kelly Ford (Co-Chair, Microsoft)</li>
<li>Mark Hakkinen (Invited Expert)</li>
<li>Simon Harper (University of Manchester)</li>
<li>Patrick Lauke (Opera Software)</li>
<li>Greg Lowney (Invited Expert)</li>
<li>Kimberly Patch (Invited Expert)</li>
<li>Jan Richards (Adaptive Technology Resource Centre, University of
Toronto)</li>
<li>Jeanne Spellman (W3C Staff Contact)</li>
</ul>
<h3><a name="previous-participants" id="previous-participants"></a>Other
previously active UAWG participants and other contributors to UAAG 2.0:</h3>
<ul>
<li>Judy Brewer (W3C)</li>
<li>Sean Hayes (Microsoft)</li>
<li>Dean Hudson (Apple)</li>
<li>Cathy Laws (IBM)</li>
<li>Peter Parente (IBM)</li>
<li>David Poehlman (Invited Expert)</li>
<li>Simon Pieters (Opera Software)</li>
<li>Henny Swan (Opera Software)</li>
<li>Gregory Rosmaita (Invited Expert)</li>
<li>David Tseng (Apple) </li>
</ul>
<p>UAAG 2.0 would not have been possible without the work of <a
href="http://www.w3.org/TR/WAI-USERAGENT/acks.html#Acknowledgments">those who
contributed to UAAG 1.0</a>.</p>
<p>This publication has been funded in part with Federal funds from the U.S.
Department of Education, National Institute on Disability and Rehabilitation
Research (NIDRR) under contract number ED-OSE-10-C-0067. The content of this
publication does not necessarily reflect the views or policies of the U.S.
Department of Education, nor does mention of trade names, commercial
products, or organizations imply endorsement by the U.S. Government. </p>
<hr />
<h2><a name="checklist" id="checklist"></a>Appendix E: Checklist </h2>
<p class="editor-notes">@@ Editors' Note: This section is still under development@@ </p>
<hr />
<h2><a name="version-comparison" id="version-comparison"></a>Appendix F:
Comparison of UAAG 1.0 guidelines to UAAG 2.0</h2>
<p class="editor-notes">@@ Editors' Note: This section is still under development@@ </p>
<div class="techs-only">
<h2><a name="alternative-content-list" id="alternative-content-list"></a>Appendix G: Alternative Content</h2>
<p>These are the elements and attributes that present 'alternative
content' relevant to Guideline 3. </p>
<p class="editor-notes">@@ Editors' Note: This needs update and permanent links as HTML5 goes to rec. Get listings of alternative content for other technologies. Think about better format for presenting it. </p>
<ul>
<li>@alt for IMG</li>
<li>@alt for AREA </li>
<li>@alt for INPUT type=image </li>
<li>@alt for EMBED </li>
<li>@longdesc for IMG </li>
<li>@longdesc for FRAME </li>
<li>@longdesc for IFRAME </li>
<li>@summary for TABLE </li>
<li>@abbr for TH </li>
<li>@title for A </li>
<li>@title for ABBR </li>
<li>@title for ACRONYM </li>
<li>@title for many other things (SPAN
<a href="http://dev.w3.org/html5/spec/Overview.html#footnotes">http://dev.w3.org/html5/spec/Overview.html#footnotes</a>) </li>
<li>@cite for Q </li>
<li>'fallback content' for OBJECT </li>
<li>'fallback content' for EMBED </li>
<li>'fallback content' for CANVAS </li>
<li>Caption tracks for VIDEO
Audio </li>
<li>Description tracks for VIDEO </li>
<li>@srcdoc for IFRAME
(<a href="http://dev.w3.org/html5/spec/Overview.html#the-iframe-element">http://dev.w3.org/html5/spec/Overview.html#the-iframe-element</a>) </li>
<li>DETAILS and SUMMARY elements
<a href="http://dev.w3.org/html5/spec/Overview.html#the-details-element">http://dev.w3.org/html5/spec/Overview.html#the-details-element</a> (? This is a
user widget for the user to get additional information provided by the
author but only available on request.) </li>
<li>@title (hint) for COMMAND
<a href="http://dev.w3.org/html5/spec/Overview.html#using-the-command-element-to-define-a-command">http://dev.w3.org/html5/spec/Overview.html#using-the-command-element-to-define-a-command</a></li>
<li>WAI role and state</li>
</ul>
</div>
</body>
</html>