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<title>Objects, Images, and Applets in HTML documents</title>
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<h1 align="center"><a name="h-13">13</a> Objects, Images, and Applets</h1>

<div class="subtoc">
<p><strong>Contents</strong></p>

<ol>
<li><a class="tocxref" href="#h-13.1">Introduction to objects, images, and
applets</a></li>

<li><a class="tocxref" href="#h-13.2">Including an image: the <samp class=
"einst2">IMG</samp> element</a></li>

<li><a class="tocxref" href="#h-13.3">Generic inclusion: the <samp class=
"einst2">OBJECT</samp> element</a>

<ol>
<li><a class="tocxref" href="#h-13.3.1">Rules for rendering objects</a></li>

<li><a class="tocxref" href="#h-13.3.2">Object initialization: the <samp class=
"einst2">PARAM</samp> element</a></li>

<li><a class="tocxref" href="#h-13.3.3">Global naming schemes for
objects</a></li>

<li><a class="tocxref" href="#h-13.3.4">Object declarations and
instantiations</a></li>
</ol>
</li>

<li><a class="tocxref" href="#h-13.4">Including an applet: the <samp class=
"einst2">APPLET</samp> element</a></li>

<li><a class="tocxref" href="#h-13.5">Notes on embedded documents</a></li>

<li><a class="tocxref" href="#h-13.6"><span class="index-def" title="image
map">Image maps</span></a>

<ol>
<li><a class="tocxref" href="#h-13.6.1">Client-side image maps: the <samp
class="einst2">MAP</samp> and <samp class="einst2">AREA</samp> elements</a>

<ul>
<li><a class="tocxref" href="#h-13.6.1.1">Client-side image map
examples</a></li>
</ul>
</li>

<li><a class="tocxref" href="#h-13.6.2">Server-side image maps</a></li>
</ol>
</li>

<li><a class="tocxref" href="#h-13.7">Visual presentation of images, objects,
and applets</a>

<ol>
<li><a class="tocxref" href="#h-13.7.1">Width and height</a></li>

<li><a class="tocxref" href="#h-13.7.2">White space around images and
objects</a></li>

<li><a class="tocxref" href="#h-13.7.3">Borders</a></li>

<li><a class="tocxref" href="#h-13.7.4">Alignment</a></li>
</ol>
</li>

<li><a class="tocxref" href="#h-13.8">How to specify alternate text</a></li>
</ol>
</div>

<h2><a name="h-13.1">13.1</a> Introduction to objects, images, and applets</h2>

<p>HTML's multimedia features allow authors to include images, applets
(programs that are automatically downloaded and run on the user's machine),
video clips, and other HTML documents in their pages.</p>

<div class="example">
<p>For example, to include a PNG image in a document, authors may write:</p>

<pre>
&lt;BODY&gt;
&lt;P&gt;Here's a closeup of the Grand Canyon:
&lt;OBJECT data="canyon.png" type="image/png"&gt;
This is a &lt;EM&gt;closeup&lt;/EM&gt; of the Grand Canyon.
&lt;/OBJECT&gt;
&lt;/BODY&gt;
</pre>
</div>

<p>Previous versions of HTML allowed authors to include images (via <a href=
"objects.html#edef-IMG" class="noxref"><samp class="einst">IMG</samp></a>) and
applets (via <a href="objects.html#edef-APPLET" class="noxref"><samp class=
"einst">APPLET</samp></a>). These elements have several limitations:</p>

<ul>
<li>They fail to solve the more general problem of how to include new and
future media types.</li>

<li>The <a href="objects.html#edef-APPLET" class="noxref"><samp class="einst">
APPLET</samp></a> element only works with Java-based applets. This element is
<a href="../conform.html#deprecated">deprecated</a> in favor of <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>.</li>

<li>They pose accessibility problems.</li>
</ul>

<p>To address these issues, HTML 4 introduces the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element, which offers an all-purpose solution to generic object inclusion. The
<a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element allows HTML authors to specify everything required by
an object for its presentation by a user agent: source code, initial values,
and run-time data. In this specification, the term "object" is used to describe
the things that people want to place in HTML documents; other commonly used
terms for these things are: applets, plug-ins, media handlers, etc.</p>

<p>The new <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> element thus subsumes some of the tasks carried out
by existing elements. Consider the following chart of functionalities:</p>

<table summary="Table summarizing which HTML elements (IMG, OBJECT, APPLET)
include images, objects, etc. in an HTML document" border>
<thead>
<tr>
<th><strong>Type of inclusion</strong></th>
<th><strong>Specific element</strong></th>
<th><strong>Generic element</strong></th>
</tr>
</thead>

<tbody>
<tr>
<td>Image</td>
<td><a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a></td>
<td><a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a></td>
</tr>

<tr>
<td>Applet</td>
<td><a href="objects.html#edef-APPLET" class="noxref"><samp class="einst">
APPLET</samp></a> <strong>(<a href=
"../conform.html#deprecated">Deprecated</a>.)</strong></td>
<td><a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a></td>
</tr>

<tr>
<td>Another HTML document</td>
<td><a href="../present/frames.html#edef-IFRAME" class="noxref"><samp class=
"einst">IFRAME</samp></a></td>
<td><a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a></td>
</tr>
</tbody>
</table>

<p>The chart indicates that each type of inclusion has a specific and a general
solution. The generic <a href="objects.html#edef-OBJECT" class="noxref"><samp
class="einst">OBJECT</samp></a> element will serve as the solution for
implementing future media types.</p>

<p><span class="index-inst" title="image::ways to include"><a name="idx-image">
To include images</a></span>, authors may use the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element or the <a href="objects.html#edef-IMG" class="noxref"><samp class=
"einst">IMG</samp></a> element.</p>

<p><span class="index-inst" title="applet::ways to include"><a name=
"idx-applet">To include applets</a></span>, authors should use the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element as the <a href="objects.html#edef-APPLET" class="noxref"><samp class=
"einst">APPLET</samp></a> element is <a href="../conform.html#deprecated">
deprecated</a>.</p>

<p><span class="index-inst" title="document::ways to include"><a name=
"idx-document">To include one HTML document in another</a></span>, authors may
use either the new <a href="../present/frames.html#edef-IFRAME" class="noxref">
<samp class="einst">IFRAME</samp></a> element or the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element. In both cases, the embedded document remains independent of the main
document. Visual user agents may present the embedded document in a distinct
window within the main document. Please consult the <a href=
"#embedded-documents">notes on embedded documents</a> for a comparison of <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> and <a href="../present/frames.html#edef-IFRAME" class=
"noxref"><samp class="einst">IFRAME</samp></a> for document inclusion.</p>

<p>Images and other included objects may have hyperlinks associated with them,
both through the standard <a href="./links.html">linking mechanisms</a>, but
also via <a href="#include-maps"><em>image maps</em></a>. An image map
specifies active geometric regions of an included object and assigns a link to
each region. When activated, these links may cause a document to be retrieved,
may run a program on the server, etc.</p>

<p>In the following sections, we discuss the various mechanisms available to
authors for multimedia inclusions and creating image maps for those
inclusions.</p>

<h2><a name="h-13.2">13.2</a> <a name="include-images">Including an image:</a>
the <a name="edef-IMG"><samp class="edef">IMG</samp></a> element</h2>

<div class="dtd-fragment">
<pre class="dtd-fragment">
&lt;!-- To avoid problems with text-only UAs as well as
   to make image content understandable and navigable
   to users of non-visual UAs, you need to provide
   a description with ALT, and avoid server-side image maps --&gt;
&lt;!ELEMENT <a href="objects.html#edef-IMG" class="noxref"><samp class=
"einst">IMG</samp></a> - O EMPTY                -- Embedded image --&gt;
&lt;!ATTLIST IMG
  <a href=
"../sgml/dtd.html#attrs">%attrs;</a>                              -- <a href=
"../sgml/dtd.html#coreattrs">%coreattrs</a>, <a href=
"../sgml/dtd.html#i18n">%i18n</a>, <a href=
"../sgml/dtd.html#events">%events</a> --
  <a href="objects.html#adef-src-IMG" class="noxref"><samp class=
"ainst-IMG">src</samp></a>         <a href=
"../sgml/dtd.html#URI">%URI;</a>          #REQUIRED -- URI of image to embed --
  <a href="objects.html#adef-alt" class="noxref"><samp class=
"ainst-IMG">alt</samp></a>         <a href=
"../sgml/dtd.html#Text">%Text;</a>         #REQUIRED -- short description --
  <a href="objects.html#adef-longdesc-IMG" class="noxref"><samp class=
"ainst-IMG">longdesc</samp></a>    <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- link to long description
                                          (complements alt) --
  <a href="objects.html#adef-name-IMG" class="noxref"><samp class=
"ainst-IMG">name</samp></a>        <a href=
"../types.html#type-cdata">CDATA</a>          #IMPLIED  -- name of image for scripting --
  <a href="objects.html#adef-height-IMG" class="noxref"><samp class=
"ainst-IMG">height</samp></a>      <a href=
"../sgml/dtd.html#Length">%Length;</a>       #IMPLIED  -- override height --
  <a href="objects.html#adef-width-IMG" class="noxref"><samp class=
"ainst-IMG">width</samp></a>       <a href=
"../sgml/dtd.html#Length">%Length;</a>       #IMPLIED  -- override width --
  <a href="objects.html#adef-usemap" class="noxref"><samp class=
"ainst-IMG">usemap</samp></a>      <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- use client-side image map --
  <a href="objects.html#adef-ismap" class="noxref"><samp class=
"ainst-IMG">ismap</samp></a>       (ismap)        #IMPLIED  -- use server-side image map --
  &gt;
</pre>
</div>

<p><em>Start tag: <strong>required</strong>, End tag: <strong>
forbidden</strong></em></p>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-src-IMG"><samp class="adef">src</samp></a> = <a href=
"../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute specifies the location of the image resource. Examples of
widely recognized image formats include GIF, JPEG, and PNG.</dd>

<dt><a name="adef-longdesc-IMG"><samp class="adef">longdesc</samp></a> = <a
href="../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute specifies a link to a long description of the image. This
description should supplement the short description provided using the <a href=
"objects.html#adef-alt" class="noxref"><samp class="ainst">alt</samp></a>
attribute. When the image has an associated <a href="#include-maps">image
map</a>, this attribute should provide information about the image map's
contents. This is particularly important for server-side image maps. Since an
<a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a> element may be within the content of an <a href=
"links.html#edef-A" class="noxref"><samp class="einst">A</samp></a> element,
the user agent's mechanism in the user interface for accessing the "longdesc"
resource of the former must be different than the mechanism for accessing the
<a href="links.html#adef-href" class="noxref"><samp class="ainst">
href</samp></a> resource of the latter.</dd>

<dt><a name="adef-name-IMG"><samp class="adef">name</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute names the element so that it may be referred to from style
sheets or scripts. <strong>Note.</strong> This attribute has been included for
backwards compatibility. Applications should use the <a href=
"global.html#adef-id" class="noxref"><samp class="ainst">id</samp></a>
attribute to identify elements.</dd>
</dl>
</div>

<div class="aref-list">
<p><em>Attributes defined elsewhere</em></p>

<ul>
<li><a href="global.html#adef-id" class="noxref"><samp class="ainst">
id</samp></a>, <a href="global.html#adef-class" class="noxref"><samp class=
"ainst">class</samp></a> (<a href=
"../struct/global.html#id-and-class">document-wide identifiers</a>)</li>

<li><a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> (<a href="#alternate-text">alternate text</a>)</li>

<li><a href="dirlang.html#adef-lang" class="noxref"><samp class="ainst">
lang</samp></a> (<a href="../struct/dirlang.html#language-info">language
information</a>), <a href="dirlang.html#adef-dir" class="noxref"><samp class=
"ainst">dir</samp></a> (<a href="../struct/dirlang.html#bidirection">text
direction</a>)</li>

<li><a href="global.html#adef-title" class="noxref"><samp class="ainst">
title</samp></a> (<a href="../struct/global.html#title">element title</a>)</li>

<li><a href="../present/styles.html#adef-style" class="noxref"><samp class=
"ainst">style</samp></a> (<a href="../present/styles.html#style-element">inline
style information</a>)</li>

<li><a href="../interact/scripts.html#adef-onclick" class="noxref"><samp class=
"ainst">onclick</samp></a>, <a href="../interact/scripts.html#adef-ondblclick"
class="noxref"><samp class="ainst">ondblclick</samp></a>, <a href=
"../interact/scripts.html#adef-onmousedown" class="noxref"><samp class="ainst">
onmousedown</samp></a>, <a href="../interact/scripts.html#adef-onmouseup"
class="noxref"><samp class="ainst">onmouseup</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseover" class="noxref"><samp class="ainst">
onmouseover</samp></a>, <a href="../interact/scripts.html#adef-onmousemove"
class="noxref"><samp class="ainst">onmousemove</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseout" class="noxref"><samp class="ainst">
onmouseout</samp></a>, <a href="../interact/scripts.html#adef-onkeypress"
class="noxref"><samp class="ainst">onkeypress</samp></a>, <a href=
"../interact/scripts.html#adef-onkeydown" class="noxref"><samp class="ainst">
onkeydown</samp></a>, <a href="../interact/scripts.html#adef-onkeyup" class=
"noxref"><samp class="ainst">onkeyup</samp></a> (<a href=
"../interact/scripts.html#events">intrinsic events</a>)</li>

<li><a href="objects.html#adef-ismap" class="noxref"><samp class="ainst">
ismap</samp></a>, <a href="objects.html#adef-usemap" class="noxref"><samp
class="ainst">usemap</samp></a> (<a href="#client-side-maps">client side image
maps</a>)</li>

<li><a href="objects.html#adef-align-IMG" class="noxref"><samp class=
"ainst-IMG">align</samp></a>, <a href="objects.html#adef-width-IMG" class=
"noxref"><samp class="ainst-IMG">width</samp></a>, <a href=
"objects.html#adef-height-IMG" class="noxref"><samp class="ainst-IMG">
height</samp></a>, <a href="objects.html#adef-border-IMG" class="noxref"><samp
class="ainst-IMG">border</samp></a>, <a href="objects.html#adef-hspace" class=
"noxref"><samp class="ainst">hspace</samp></a>, <a href=
"objects.html#adef-vspace" class="noxref"><samp class="ainst">vspace</samp></a>
(<a href="#visual">visual presentation of objects, images, and
applets</a>)</li>
</ul>
</div>

<p>The <a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a> element embeds an image in the current document at the location
of the element's definition. The <a href="objects.html#edef-IMG" class=
"noxref"><samp class="einst">IMG</samp></a> element has no content; it is
usually replaced inline by the image designated by the <a href=
"objects.html#adef-src-IMG" class="noxref"><samp class="ainst-IMG">
src</samp></a> attribute, the exception being for left or right-aligned images
that are <a href="../present/graphics.html#floating">"floated"</a> out of
line.</p>

<div class="example">
<p>In an earlier example, we defined a link to a family photo. Here, we insert
the photo directly into the current document:</p>

<pre>
&lt;BODY&gt;
&lt;P&gt;I just returned from vacation! Here's a photo of my family at the lake:
&lt;IMG src="http://www.somecompany.com/People/Ian/vacation/family.png"
     alt="A photo of my family at the lake."&gt;
&lt;/BODY&gt;
</pre>

<p>This inclusion may also be achieved with the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element as follows:</p>

<pre>
&lt;BODY&gt;
&lt;P&gt;I just returned from vacation! Here's a photo of my family at the lake:
&lt;OBJECT data="http://www.somecompany.com/People/Ian/vacation/family.png"
        type="image/png"&gt;
A photo of my family at the lake.
&lt;/OBJECT&gt;
&lt;/BODY&gt;
</pre>
</div>

<p>The <a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> attribute specifies alternate text that is rendered when the
image cannot be displayed (see below for information on <a href=
"#alternate-text">how to specify alternate text</a> ). User agents must render
alternate text when they cannot support images, they cannot support a certain
image type or when they are configured not to display images.</p>

<div class="example">
<p>The following example shows how the <samp class="ainst">longdesc</samp>
attribute can be used to link to a richer description:</p>

<pre>
&lt;BODY&gt;
&lt;P&gt;
&lt;IMG src="sitemap.gif"
     alt="HP Labs Site Map"
     longdesc="sitemap.html"&gt;
&lt;/BODY&gt;
</pre>

<p>The <a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> attribute provides a short description of the image. This should
be sufficient to allow users to decide whether they want to follow the link
given by the <span class="index-inst" title="long image description::relation
to alt text|image::long description of|accessibility::long image description">
<a name="idx-long_image_description"><samp class="ainst">
longdesc</samp></a></span> attribute to the longer description, here
"sitemap.html".</p>
</div>

<p>Please consult the section on the <a href="#visual">visual presentation of
objects, images, and applets</a> for information about image size, alignment,
and borders.</p>

<h2><a name="h-13.3">13.3</a> <a name="include-objects">Generic inclusion:</a>
the <a name="edef-OBJECT"><samp class="edef">OBJECT</samp></a> element</h2>

<div class="dtd-fragment">
<pre class="dtd-fragment">
&lt;!ELEMENT <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> - - (PARAM | <a href=
"../sgml/dtd.html#flow">%flow;</a>)*
 -- generic embedded object --&gt;
&lt;!ATTLIST OBJECT
  <a href=
"../sgml/dtd.html#attrs">%attrs;</a>                              -- <a href=
"../sgml/dtd.html#coreattrs">%coreattrs</a>, <a href=
"../sgml/dtd.html#i18n">%i18n</a>, <a href=
"../sgml/dtd.html#events">%events</a> --
  <a href="objects.html#adef-declare" class="noxref"><samp class=
"ainst-OBJECT">declare</samp></a>     (declare)      #IMPLIED  -- declare but don't instantiate flag --
  <a href="objects.html#adef-classid" class="noxref"><samp class=
"ainst-OBJECT">classid</samp></a>     <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- identifies an implementation --
  <a href="objects.html#adef-codebase-OBJECT" class="noxref"><samp class=
"ainst-OBJECT">codebase</samp></a>    <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- base URI for classid, data, archive--
  <a href="objects.html#adef-data" class="noxref"><samp class=
"ainst-OBJECT">data</samp></a>        <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- reference to object's data --
  <a href="objects.html#adef-type-OBJECT" class="noxref"><samp class=
"ainst-OBJECT">type</samp></a>        <a href=
"../sgml/dtd.html#ContentType">%ContentType;</a>  #IMPLIED  -- content type for data --
  <a href="objects.html#adef-codetype" class="noxref"><samp class=
"ainst-OBJECT">codetype</samp></a>    <a href=
"../sgml/dtd.html#ContentType">%ContentType;</a>  #IMPLIED  -- content type for code --
  <a href="objects.html#adef-archive-OBJECT" class="noxref"><samp class=
"ainst-OBJECT">archive</samp></a>     <a href=
"../types.html#type-cdata">CDATA</a>          #IMPLIED  -- space-separated list of URIs --
  <a href="objects.html#adef-standby" class="noxref"><samp class=
"ainst-OBJECT">standby</samp></a>     <a href=
"../sgml/dtd.html#Text">%Text;</a>         #IMPLIED  -- message to show while loading --
  <a href="objects.html#adef-height-IMG" class="noxref"><samp class=
"ainst-IMG">height</samp></a>      <a href=
"../sgml/dtd.html#Length">%Length;</a>       #IMPLIED  -- override height --
  <a href="objects.html#adef-width-IMG" class="noxref"><samp class=
"ainst-IMG">width</samp></a>       <a href=
"../sgml/dtd.html#Length">%Length;</a>       #IMPLIED  -- override width --
  <a href="objects.html#adef-usemap" class="noxref"><samp class=
"ainst-OBJECT">usemap</samp></a>      <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- use client-side image map --
  <a href="../interact/forms.html#adef-name-INPUT" class="noxref"><samp class=
"ainst-INPUT">name</samp></a>        <a href=
"../types.html#type-cdata">CDATA</a>          #IMPLIED  -- submit as part of form --
  <a href="../interact/forms.html#adef-tabindex" class="noxref"><samp class=
"ainst-OBJECT">tabindex</samp></a>    <a href=
"../types.html#type-number">NUMBER</a>         #IMPLIED  -- position in tabbing order --
  &gt;
</pre>
</div>

<p><em>Start tag: <strong>required</strong>, End tag: <strong>
required</strong></em></p>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-classid"><samp class="adef">classid</samp></a> = <a href=
"../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute may be used to specify the location of an object's
implementation via a URI. It may be used together with, or as an alternative to
the <a href="objects.html#adef-data" class="noxref"><samp class="ainst">
data</samp></a> attribute, depending on the type of object involved.</dd>

<dt><a name="adef-codebase-OBJECT"><samp class="adef">codebase</samp></a> = <a
href="../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute specifies the base path used to resolve relative URIs
specified by the <a href="objects.html#adef-classid" class="noxref"><samp
class="ainst">classid</samp></a>, <a href="objects.html#adef-data" class=
"noxref"><samp class="ainst">data</samp></a>, and <a href=
"objects.html#adef-archive-OBJECT" class="noxref"><samp class="ainst-OBJECT">
archive</samp></a> attributes. When absent, its default value is the base URI
of the current document.</dd>

<dt><a name="adef-codetype"><samp class="adef">codetype</samp></a> = <a href=
"../types.html#type-content-type"><em>content-type</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the content type of data expected when downloading
the object specified by <a href="objects.html#adef-classid" class="noxref">
<samp class="ainst">classid</samp></a>. This attribute is optional but
recommended when <a href="objects.html#adef-classid" class="noxref"><samp
class="ainst">classid</samp></a> is specified since it allows the user agent to
avoid loading information for unsupported content types. When absent, it
defaults to the value of the <samp class="ainst">type</samp> attribute.</dd>

<dt><a name="adef-data"><samp class="adef">data</samp></a> = <a href=
"../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute may be used to specify the location of the object's data,
for instance image data for objects defining images, or more generally, a
serialized form of an object which can be used to recreate it. If given as a
relative URI, it should be interpreted relative to the <samp class="ainst">
codebase</samp> attribute.</dd>

<dt><a name="adef-type-OBJECT"><samp class="adef">type</samp></a> = <a href=
"../types.html#type-content-type"><em>content-type</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the content type for the data specified by <a
href="objects.html#adef-data" class="noxref"><samp class="ainst">
data</samp></a>. This attribute is optional but recommended when <a href=
"objects.html#adef-data" class="noxref"><samp class="ainst">data</samp></a> is
specified since it allows the user agent to avoid loading information for
unsupported content types. If the value of this attribute differs from the HTTP
Content-Type returned by the server when the object is retrieved, the HTTP
Content-Type takes precedence.</dd>

<dt><a name="adef-archive-OBJECT"><samp class="adef">archive</samp></a> = <a
href="../types.html#type-uri"><em>uri-list</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute may be used to specify a <em>space-separated</em> list of
URIs for archives containing resources relevant to the object, which may
include the resources specified by the <a href="objects.html#adef-classid"
class="noxref"><samp class="ainst">classid</samp></a> and <a href=
"objects.html#adef-data" class="noxref"><samp class="ainst">data</samp></a>
attributes. Preloading archives will generally result in reduced load times for
objects. Archives specified as relative URIs should be interpreted relative to
the <samp class="ainst">codebase</samp> attribute.</dd>

<dt><a name="adef-declare"><samp class="adef">declare</samp></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>When present, this boolean attribute makes the current <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
definition a declaration only. The object must be instantiated by a subsequent
<a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> definition referring to this declaration.</dd>

<dt><a name="adef-standby"><samp class="adef">standby</samp></a> = <a href=
"../types.html#type-text"><em>text</em></a> <a href=
"../types.html#case-sensitive">[CS]</a></dt>

<dd>This attribute specifies a message that a user agent may render while
loading the object's implementation and data.</dd>
</dl>
</div>

<div class="aref-list">
<p><em>Attributes defined elsewhere</em></p>

<ul>
<li><a href="global.html#adef-id" class="noxref"><samp class="ainst">
id</samp></a>, <a href="global.html#adef-class" class="noxref"><samp class=
"ainst">class</samp></a> (<a href=
"../struct/global.html#id-and-class">document-wide identifiers</a>)</li>

<li><a href="dirlang.html#adef-lang" class="noxref"><samp class="ainst">
lang</samp></a> (<a href="../struct/dirlang.html#language-info">language
information</a>), <a href="dirlang.html#adef-dir" class="noxref"><samp class=
"ainst">dir</samp></a> (<a href="../struct/dirlang.html#bidirection">text
direction</a>)</li>

<li><a href="global.html#adef-title" class="noxref"><samp class="ainst">
title</samp></a> (<a href="../struct/global.html#title">element title</a>)</li>

<li><a href="../present/styles.html#adef-style" class="noxref"><samp class=
"ainst">style</samp></a> (<a href="../present/styles.html#style-element">inline
style information</a>)</li>

<li><a href="../interact/scripts.html#adef-onclick" class="noxref"><samp class=
"ainst">onclick</samp></a>, <a href="../interact/scripts.html#adef-ondblclick"
class="noxref"><samp class="ainst">ondblclick</samp></a>, <a href=
"../interact/scripts.html#adef-onmousedown" class="noxref"><samp class="ainst">
onmousedown</samp></a>, <a href="../interact/scripts.html#adef-onmouseup"
class="noxref"><samp class="ainst">onmouseup</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseover" class="noxref"><samp class="ainst">
onmouseover</samp></a>, <a href="../interact/scripts.html#adef-onmousemove"
class="noxref"><samp class="ainst">onmousemove</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseout" class="noxref"><samp class="ainst">
onmouseout</samp></a>, <a href="../interact/scripts.html#adef-onkeypress"
class="noxref"><samp class="ainst">onkeypress</samp></a>, <a href=
"../interact/scripts.html#adef-onkeydown" class="noxref"><samp class="ainst">
onkeydown</samp></a>, <a href="../interact/scripts.html#adef-onkeyup" class=
"noxref"><samp class="ainst">onkeyup</samp></a> (<a href=
"../interact/scripts.html#events">intrinsic events</a>)</li>

<li><a href="../interact/forms.html#adef-tabindex" class="noxref"><samp class=
"ainst">tabindex</samp></a> (<a href=
"../interact/forms.html#tabbing-navigation">tabbing navigation</a>)</li>

<li><a href="objects.html#adef-usemap" class="noxref"><samp class="ainst">
usemap</samp></a> (<a href="#client-side-maps">client side image maps</a>)</li>

<li><a href="../interact/forms.html#adef-name-INPUT" class="noxref"><samp
class="ainst-INPUT">name</samp></a> (<a href=
"../interact/forms.html#submit-format">form submission</a>)</li>

<li><a href="objects.html#adef-align-IMG" class="noxref"><samp class=
"ainst-IMG">align</samp></a>, <a href="objects.html#adef-width-IMG" class=
"noxref"><samp class="ainst-IMG">width</samp></a>, <a href=
"objects.html#adef-height-IMG" class="noxref"><samp class="ainst-IMG">
height</samp></a>, <a href="objects.html#adef-border-IMG" class="noxref"><samp
class="ainst-IMG">border</samp></a>, <a href="objects.html#adef-hspace" class=
"noxref"><samp class="ainst">hspace</samp></a>, <a href=
"objects.html#adef-vspace" class="noxref"><samp class="ainst">vspace</samp></a>
(<a href="#visual">visual presentation of objects, images, and
applets</a>)</li>
</ul>
</div>

<p><span class="index-inst" title="object::generic inclusion|including an
object"><a name="idx-object">Most user agents have built-in
mechanisms</a></span> for rendering common data types such as text, GIF images,
colors, fonts, and a handful of graphic elements. To render data types they
don't support natively, user agents generally run external applications. The <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element allows authors to control whether data should be
rendered externally or by some program, specified by the author, that renders
the data within the user agent.</p>

<p>In the most general case, an author may need to specify three types of
information:</p>

<ul>
<li>The implementation of the included object. For instance, if the included
object is a clock applet, the author must indicate the location of the applet's
executable code.</li>

<li>The data to be rendered. For instance, if the included object is a program
that renders font data, the author must indicate the location of that
data.</li>

<li>Additional values required by the object at run-time. For example, some
applets may require initial values for parameters.</li>
</ul>

<p>The <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element allows authors to specify all three types of data,
but authors may not have to specify all three at once. For example, some
objects may not require data (e.g., a self-contained applet that performs a
small animation). Others may not require run-time initialization. Still others
may not require additional implementation information, i.e., the user agent
itself may already know how to render that type of data (e.g., GIF images).</p>

<p><span class="index-inst" title="object::locating implementation and data"><a
name="idx-object-1">Authors specify an object's implementation</a></span> and
the location of the data to be rendered via the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element. To specify run-time values, however, authors use the <a href=
"objects.html#edef-PARAM" class="noxref"><samp class="einst">PARAM</samp></a>
element, which is discussed in the section on <a href="#object-init">object
initialization.</a></p>

<p><span class="index-inst" title="object::in HEAD">The <a name="idx-object-2"
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element may also appear in the content</span> of the <a href=
"global.html#edef-HEAD" class="noxref"><samp class="einst">HEAD</samp></a>
element. Since user agents generally do not render elements in the <a href=
"global.html#edef-HEAD" class="noxref"><samp class="einst">HEAD</samp></a>,
authors should ensure that any <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a> elements in the <a href=
"global.html#edef-HEAD" class="noxref"><samp class="einst">HEAD</samp></a> do
not specify content that may be rendered. Please consult the section on <a
href="../present/frames.html#sharing-frame-data">sharing frame data</a> for an
example of including the <a href="objects.html#edef-OBJECT" class="noxref">
<samp class="einst">OBJECT</samp></a> element in the <a href=
"global.html#edef-HEAD" class="noxref"><samp class="einst">HEAD</samp></a>
element.</p>

<p>Please consult the section on <a href=
"../interact/forms.html#form-controls">form controls</a> for information about
<a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> elements in forms.</p>

<p>This document does not specify the behavior of <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
elements that use both the <a href="objects.html#adef-classid" class="noxref">
<samp class="ainst">classid</samp></a> attribute to identify an implementation
and the <a href="objects.html#adef-data" class="noxref"><samp class="ainst">
data</samp></a> attribute to specify data for that implementation. In order to
ensure portability, authors should use the <a href="objects.html#edef-PARAM"
class="noxref"><samp class="einst">PARAM</samp></a> element to tell
implementations where to retrieve additional data.</p>

<h3><a name="h-13.3.1">13.3.1</a> <span class="index-inst" title=
"object::fallback rendering of|object::rules for embedded"><a name=
"idx-object-3">Rules for rendering objects</a></span></h3>

<p>A user agent must interpret an <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a> element according to the
following precedence rules:</p>

<ol>
<li>The user agent must first try to render the object. It should not render
the element's contents, but it must examine them in case the element contains
any direct children that are <a href="objects.html#edef-PARAM" class="noxref">
<samp class="einst">PARAM</samp></a> elements (see <a href="#object-init">
object initialization</a>) or <a href="objects.html#edef-MAP" class="noxref">
<samp class="einst">MAP</samp></a> elements (see <a href="#client-side-maps">
client-side image maps</a>).</li>

<li>If the user agent is not able to render the object for whatever reason
(configured not to, lack of resources, wrong architecture, etc.), it must try
to render its contents.</li>
</ol>

<p><span class="index-inst" title="object::in HEAD"><a name="idx-object-5">
Authors should not include</a></span> content in <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
elements that appear in the <a href="global.html#edef-HEAD" class="noxref">
<samp class="einst">HEAD</samp></a> element.</p>

<div class="example">
<p>In the following example, we insert an analog clock applet in a document via
the <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element. The applet, written in the Python language, requires
no additional data or run-time values. The <a href="objects.html#adef-classid"
class="noxref"><samp class="ainst">classid</samp></a> attribute specifies the
location of the applet:</p>

<pre>

&lt;P&gt;&lt;OBJECT classid="http://www.miamachina.it/analogclock.py"&gt;
&lt;/OBJECT&gt;
</pre>

<p>Note that the clock will be rendered as soon as the user agent interprets
this <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> declaration. It is possible to delay rendering of an object
by first <em>declaring</em> the object (described below).</p>

<p>Authors should complete this declaration by including alternate text as the
contents of <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> in case the user agent cannot render the clock.</p>

<pre>

&lt;P&gt;&lt;OBJECT classid="http://www.miamachina.it/analogclock.py"&gt;
An animated clock.
&lt;/OBJECT&gt;
</pre>
</div>

<p><span class="index-inst" title="accessibility::alternate object content"><a
name="idx-accessibility-1">One significant consequence</a></span> of the <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element's design is that it offers a mechanism for specifying
alternate object renderings; each embedded <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a> declaration may specify
alternate content types. If a user agent cannot render the outermost <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>, it tries to render the contents, which may be another <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element, etc.</p>

<div class="example">
<p>In the following example, we embed several <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
declarations to illustrate how alternate renderings work. A user agent will
attempt to render the first <a href="objects.html#edef-OBJECT" class="noxref">
<samp class="einst">OBJECT</samp></a> element it can, in the following order:
(1) an Earth applet written in the Python language, (2) an MPEG animation of
the Earth, (3) a GIF image of the Earth, (4) alternate text.</p>

<pre>
&lt;P&gt;                 &lt;!-- First, try the Python applet --&gt;
&lt;OBJECT title="The Earth as seen from space"
        classid="http://www.observer.mars/TheEarth.py"&gt;
                    &lt;!-- Else, try the MPEG video --&gt;
  &lt;OBJECT data="TheEarth.mpeg" type="application/mpeg"&gt;
                    &lt;!-- Else, try the GIF image --&gt;
    &lt;OBJECT data="TheEarth.gif" type="image/gif"&gt;
                    &lt;!-- Else render the text --&gt;
     The &lt;STRONG&gt;Earth&lt;/STRONG&gt; as seen from space.
    &lt;/OBJECT&gt;
  &lt;/OBJECT&gt;
&lt;/OBJECT&gt;
</pre>

<p>The outermost declaration specifies an applet that requires no data or
initial values. The second declaration specifies an MPEG animation and, since
it does not define the location of an implementation to handle MPEG, relies on
the user agent to handle the animation. We also set the <samp class="ainst">
type</samp> attribute so that a user agent that knows it cannot render MPEG
will not bother to retrieve "TheEarth.mpeg" from the network. The third
declaration specifies the location of a GIF file and furnishes alternate text
in case all other mechanisms fail.</p>
</div>

<div class="note">
<p><em><strong>Inline vs. external data.</strong> Data to be rendered may be
supplied in two ways: inline and from an external resource. While the former
method will generally lead to faster rendering, it is not convenient when
rendering large quantities of data.</em></p>

<p><em>Here's an example that illustrates how inline data may be fed to an <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>:</em></p>

<pre>
&lt;P&gt;
&lt;OBJECT id="clock1"
        classid="clsid:663C8FEF-1EF9-11CF-A3DB-080036F12502"
        data="data:application/x-oleobject;base64, <em>...base64 data...</em>"&gt;
    A clock.
&lt;/OBJECT&gt;
</pre>
</div>

<p>Please consult the section on the <a href="#visual">visual presentation of
objects, images, and applets</a> for information about object size, alignment,
and borders.</p>

<h3><a name="h-13.3.2">13.3.2</a> <span class="index-inst" title=
"object::initialization"><a name="object-init">Object
initialization:</a></span> the <a name="edef-PARAM"><samp class="edef">
PARAM</samp></a> element</h3>

<div class="dtd-fragment">
<pre class="dtd-fragment">
&lt;!ELEMENT <a href="objects.html#edef-PARAM" class="noxref"><samp class=
"einst">PARAM</samp></a> - O EMPTY              -- named property value --&gt;
&lt;!ATTLIST PARAM
  <a href="global.html#adef-id" class="noxref"><samp class=
"ainst">id</samp></a>          <a href=
"../types.html#type-id">ID</a>             #IMPLIED  -- document-wide unique id --
  <a href="objects.html#adef-name-PARAM" class="noxref"><samp class=
"ainst-PARAM">name</samp></a>        <a href=
"../types.html#type-cdata">CDATA</a>          #REQUIRED -- property name --
  <a href="objects.html#adef-value-PARAM" class="noxref"><samp class=
"ainst-PARAM">value</samp></a>       <a href=
"../types.html#type-cdata">CDATA</a>          #IMPLIED  -- property value --
  <a href="objects.html#adef-valuetype" class="noxref"><samp class=
"ainst-PARAM">valuetype</samp></a>   (DATA|REF|OBJECT) DATA   -- How to interpret value --
  <a href="objects.html#adef-type-PARAM" class="noxref"><samp class=
"ainst-PARAM">type</samp></a>        <a href=
"../sgml/dtd.html#ContentType">%ContentType;</a>  #IMPLIED  -- content type for value
                                          when valuetype=ref --
  &gt;
</pre>
</div>

<p><em>Start tag: <strong>required</strong>, End tag: <strong>
forbidden</strong></em></p>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-name-PARAM"><samp class="adef">name</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a></dt>

<dd>This attribute defines the name of a run-time parameter, assumed to be
known by the inserted object. Whether the property name is case-sensitive
depends on the specific object implementation.</dd>

<dt><a name="adef-value-PARAM"><samp class="adef">value</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a></dt>

<dd>This attribute specifies the value of a run-time parameter specified by <a
href="objects.html#adef-name-PARAM" class="noxref"><samp class="ainst-PARAM">
name</samp></a>. Property values have no meaning to HTML; their meaning is
determined by the object in question.</dd>

<dt><a name="adef-valuetype"><samp class="adef">valuetype</samp></a> = <samp>
data|ref|object</samp> <a href="../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the type of the <samp>value</samp> attribute.
Possible values:

<ul>
<li><samp>data:</samp> This is default value for the attribute. It means that
the value specified by <samp class="ainst">value</samp> will be evaluated and
passed to the object's implementation as a string.</li>

<li><samp>ref:</samp> The value specified by <samp class="ainst">value</samp>
is a URI that designates a resource where run-time values are stored. This
allows support tools to identify URIs given as parameters. The URI must be
passed to the object <strong>as is</strong>, i.e., unresolved.</li>

<li><samp>object:</samp> The value specified by <samp class="ainst">
value</samp> is an identifier that refers to an <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
declaration in the same document. The identifier must be the value of the <a
href="global.html#adef-id" class="noxref"><samp class="ainst">id</samp></a>
attribute set for the declared <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a> element.</li>
</ul>
</dd>

<dt><a name="adef-type-PARAM"><samp class="adef">type</samp></a> = <a href=
"../types.html#type-content-type"><em>content-type</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the content type of the resource designated by the
<samp class="ainst">value</samp> attribute <strong>only</strong> in the case
where <a href="objects.html#adef-valuetype" class="noxref"><samp class="ainst">
valuetype</samp></a> is set to "ref". This attribute thus specifies for the
user agent, the type of values that will be found at the URI designated by
<samp class="ainst">value</samp>.</dd>
</dl>
</div>

<div class="aref-list">
<p><em>Attributes defined elsewhere</em></p>

<ul>
<li><a href="global.html#adef-id" class="noxref"><samp class="ainst">
id</samp></a> (<a href="../struct/global.html#id-and-class">document-wide
identifiers</a>)</li>
</ul>
</div>

<p><a href="objects.html#edef-PARAM" class="noxref"><samp class="einst">
PARAM</samp></a> elements specify a set of values that may be required by an
object at run-time. Any number of <a href="objects.html#edef-PARAM" class=
"noxref"><samp class="einst">PARAM</samp></a> elements may appear in the
content of an <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> or <a href="objects.html#edef-APPLET" class="noxref">
<samp class="einst">APPLET</samp></a> element, in any order, but must be placed
at the start of the content of the enclosing <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a> or <a href=
"objects.html#edef-APPLET" class="noxref"><samp class="einst">APPLET</samp></a>
element.</p>

<p>The syntax of names and values is assumed to be understood by the object's
implementation. This document does not specify how user agents should retrieve
name/value pairs nor how they should interpret parameter names that appear
twice.</p>

<div class="example">
<p>We return to the clock example to illustrate the use of <a href=
"objects.html#edef-PARAM" class="noxref"><samp class="einst">PARAM</samp></a>:
suppose that the applet is able to handle two run-time parameters that define
its initial height and width. We can set the initial dimensions to 40x40 pixels
with two <a href="objects.html#edef-PARAM" class="noxref"><samp class="einst">
PARAM</samp></a> elements.</p>

<pre>

&lt;P&gt;&lt;OBJECT classid="http://www.miamachina.it/analogclock.py"&gt;
&lt;PARAM name="height" value="40" valuetype="data"&gt;
&lt;PARAM name="width" value="40" valuetype="data"&gt;
This user agent cannot render Python applications.
&lt;/OBJECT&gt;
</pre>
</div>

<div class="example">
<p>In the following example, run-time data for the object's "Init_values"
parameter is specified as an external resource (a GIF file). The value of the
<a href="objects.html#adef-valuetype" class="noxref"><samp class="ainst">
valuetype</samp></a> attribute is thus set to "ref" and the <samp class=
"ainst">value</samp> is a URI designating the resource.</p>

<pre>
&lt;P&gt;&lt;OBJECT classid="http://www.gifstuff.com/gifappli"
       standby="Loading Elvis..."&gt;
&lt;PARAM name="Init_values"
       value="./images/elvis.gif"&gt;
       valuetype="ref"&gt;
&lt;/OBJECT&gt;
</pre>

<p>Note that we have also set the <a href="objects.html#adef-standby" class=
"noxref"><samp class="ainst-OBJECT">standby</samp></a> attribute so that the
user agent may display a message while the rendering mechanism loads.</p>
</div>

<p>When an <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> element is rendered, user agents must search the
content for only those <a href="objects.html#edef-PARAM" class="noxref"><samp
class="einst">PARAM</samp></a> elements that are direct children and "feed"
them to the <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a>.</p>

<div class="example">
<p>Thus, in the following example, if "obj1" is rendered, "param1" applies to
"obj1" (and not "obj2"). If "obj1" is not rendered and "obj2" is, "param1" is
ignored, and "param2" applies to "obj2". If neither <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
is rendered, neither <a href="objects.html#edef-PARAM" class="noxref"><samp
class="einst">PARAM</samp></a> applies.</p>

<pre>
&lt;P&gt;
&lt;OBJECT id="obj1"&gt;
   &lt;PARAM name="param1"&gt;
   &lt;OBJECT id="obj2"&gt;
      &lt;PARAM name="param2"&gt;
   &lt;/OBJECT&gt;
&lt;/OBJECT&gt;
</pre>
</div>

<h3><a name="h-13.3.3">13.3.3</a> <span class="index-inst" title=
"object::naming schemes for"><a name="idx-object-7">Global naming schemes for
objects</a></span></h3>

<p>The location of an object's implementation is given by a URI. As we
discussed in the <a href="../intro/intro.html#intro-uris">introduction to
URIs</a>, the first segment of an absolute URI specifies the naming scheme used
to transfer the data designated by the URI. For HTML documents, this scheme is
frequently "http". Some applets might employ other naming schemes. For
instance, when specifying a Java applet, authors may use URIs that begin with
"java" and for ActiveX applets, authors may use "clsid".</p>

<div class="example">
<p>In the following example, we insert a Java applet into an HTML document.</p>

<pre>
&lt;P&gt;&lt;OBJECT classid="java:program.start"&gt;
&lt;/OBJECT&gt;
</pre>
</div>

<p>By setting the <a href="objects.html#adef-codetype" class="noxref"><samp
class="ainst">codetype</samp></a> attribute, a user agent can decide whether to
retrieve the Java application based on its ability to do so.</p>

<pre>
&lt;OBJECT codetype="application/java-archive"
        classid="java:program.start"&gt;
&lt;/OBJECT&gt;
</pre>

<p>Some rendering schemes require additional information to identify their
implementation and must be told where to find that information. Authors may
give path information to the object's implementation via the <a href=
"objects.html#adef-codebase-APPLET" class="noxref"><samp class="ainst-APPLET">
codebase</samp></a> attribute.</p>

<pre>
&lt;OBJECT codetype="application/java-archive"
        classid="java:program.start"&gt;
        codebase="http://foooo.bar.com/java/myimplementation/"
&lt;/OBJECT&gt;
</pre>

<div class="example">
<p>The following example specifies (with the <a href=
"objects.html#adef-classid" class="noxref"><samp class="ainst">
classid</samp></a> attribute) an ActiveX object via a URI that begins with the
naming scheme "clsid". The <a href="objects.html#adef-data" class="noxref">
<samp class="ainst-OBJECT">data</samp></a> attribute locates the data to render
(another clock).</p>

<pre>
&lt;P&gt;&lt;OBJECT classid="clsid:663C8FEF-1EF9-11CF-A3DB-080036F12502"
        data="http://www.acme.com/ole/clock.stm"&gt;
This application is not supported.
&lt;/OBJECT&gt;
</pre>
</div>

<h3><a name="h-13.3.4">13.3.4</a> <span class="index-inst" title=
"object::statically declared"><a name="object-declare">Object declarations and
instantiations</a></span></h3>

The preceding examples have only illustrated isolated object definitions. When
a document is to contain more than one instance of the same object, it is
possible to separate the declaration of the object from its instantiations.
Doing so has several advantages:

<ul>
<li>Data may be retrieved from the network by the user agent <em>one time</em>
(during the declaration) and reused for each instantiation.</li>

<li>It is possible to instantiate an object from a location other than the
object's declaration, for example, from a link.</li>

<li>It is possible to specify objects as run-time data for other objects.</li>
</ul>

<p>To declare an object so that it is not executed when read by the user agent,
set the boolean <a href="objects.html#adef-declare" class="noxref"><samp class=
"ainst">declare</samp></a> attribute in the <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a> element. At the same time,
authors must identify the declaration by setting the <a href=
"global.html#adef-id" class="noxref"><samp class="ainst">id</samp></a>
attribute in the <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> element to a unique value. Later instantiations of
the object will refer to this identifier.</p>

<p>A declared <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> must appear in a document before the first instance
of that <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>.</p>

<p>An object defined with the <a href="objects.html#adef-declare" class=
"noxref"><samp class="ainst">declare</samp></a> attribute is instantiated every
time an element that refers to that object requires it to be rendered (e.g., a
link that refers to it is activated, an object that refers to it is activated,
etc.).</p>

<div class="example">
<p>In the following example, we declare an <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a> and cause it to be
instantiated by referring to it from a link. Thus, the object can be activated
by clicking on some highlighted text, for example.</p>

<pre>
&lt;P&gt;&lt;OBJECT declare
        id="earth.declaration"
        data="TheEarth.mpeg"
        type="application/mpeg"&gt;
   The &lt;STRONG&gt;Earth&lt;/STRONG&gt; as seen from space.
&lt;/OBJECT&gt;
<em>...later in the document...</em>
&lt;P&gt;A neat &lt;A href="#earth.declaration"&gt; animation of The Earth!&lt;/A&gt;
</pre>
</div>

<div class="example">
<p>The following example illustrates how to specify run-time values that are
other objects. In this example, we send text (a poem, in fact) to a
hypothetical mechanism for viewing poems. The object recognizes a run-time
parameter named "font" (say, for rendering the poem text in a certain font).
The value for this parameter is itself an object that inserts (but does not
render) the font object. The relationship between the font object and the poem
viewer object is achieved by (1) assigning the <a href="global.html#adef-id"
class="noxref"><samp class="ainst">id</samp></a> "tribune" to the font object
declaration and (2) referring to it from the <a href="objects.html#edef-PARAM"
class="noxref"><samp class="einst">PARAM</samp></a> element of the poem viewer
object (with <a href="objects.html#adef-valuetype" class="noxref"><samp class=
"ainst">valuetype</samp></a> and <samp class="ainst">value</samp>).</p>

<pre>
&lt;P&gt;&lt;OBJECT declare
     id="tribune"
     type="application/x-webfont"
     data="tribune.gif"&gt;
&lt;/OBJECT&gt;
<em>...view the poem in KublaKhan.txt here...</em>
&lt;P&gt;&lt;OBJECT classid="http://foo.bar.com/poem_viewer"
           data="KublaKhan.txt"&gt;
&lt;PARAM name="font" valuetype="object" value="#tribune"&gt;
&lt;P&gt;You're missing a really cool poem viewer ...
&lt;/OBJECT&gt;
</pre>
</div>

<p>User agents that don't support the <a href="objects.html#adef-declare"
class="noxref"><samp class="ainst">declare</samp></a> attribute must render the
contents of the <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> declaration.</p>

<h2><a name="h-13.4">13.4</a> <a name="include-applets">Including an
applet</a>: the <a name="edef-APPLET"><samp class="edef">APPLET</samp></a>
element</h2>

<strong>APPLET is <a href="../conform.html#deprecated">deprecated (with all its
attributes)</a> in favor of <a href="objects.html#edef-OBJECT" class="noxref">
<samp class="einst">OBJECT</samp></a>.</strong>

<p>See the <a href="../sgml/loosedtd.html#applet">Transitional DTD</a> for the
formal definition.</p>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-codebase-APPLET"><samp class="adef">codebase</samp></a> = <a
href="../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute specifies the base URI for the applet. If this attribute is
not specified, then it defaults the same base URI as for the current document.
Values for this attribute may only refer to subdirectories of the directory
containing the current document. <span class="note"><em><strong>Note.</strong>
While the restriction on subdirectories is a departure from common practice and
the HTML 3.2 specification, the HTML Working Group has chosen to leave the
restriction in this version of the specification for security
reasons.</em></span></dd>

<dt><a name="adef-code"><samp class="adef">code</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a> <a href=
"../types.html#case-sensitive">[CS]</a></dt>

<dd>This attribute specifies either the name of the class file that contains
the applet's compiled applet subclass or the path to get the class, including
the class file itself. It is interpreted with respect to the applet's codebase.
One of <a href="objects.html#adef-code" class="noxref"><samp class="ainst">
code</samp></a> or <a href="objects.html#adef-object" class="noxref"><samp
class="ainst">object</samp></a> must be present.</dd>

<dt><a name="adef-name-APPLET"><samp class="adef">name</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a> <a href=
"../types.html#case-sensitive">[CS]</a></dt>

<dd>This attribute specifies a name for the applet instance, which makes it
possible for applets on the same page to find (and communicate with) each
other.</dd>

<dt><a name="adef-archive-APPLET"><samp class="adef">archive</samp></a> = <a
href="../types.html#type-uri"><em>uri-list</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute specifies a <em>comma-separated</em> list of URIs for
archives containing classes and other resources that will be "preloaded". The
classes are loaded using an instance of an AppletClassLoader with the given <a
href="objects.html#adef-codebase-APPLET" class="noxref"><samp class=
"ainst-APPLET">codebase</samp></a>. Relative URIs for archives are interpreted
with respect to the applet's codebase. Preloading resources can significantly
improve the performance of applets.</dd>

<dt><a name="adef-object"><samp class="adef">object</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a> <a href=
"../types.html#case-sensitive">[CS]</a></dt>

<dd>This attribute names a resource containing a serialized representation of
an applet's state. It is interpreted relative to the applet's codebase. The
serialized data contains the applet's class name but not the implementation.
The class name is used to retrieve the implementation from a class file or
archive.

<p>When the applet is "deserialized" the <samp>start()</samp> method is invoked
but not the <samp>init()</samp> method. Attributes valid when the original
object was serialized are <strong>not</strong> restored. Any attributes passed
to this <a href="objects.html#edef-APPLET" class="noxref"><samp class="einst">
APPLET</samp></a> instance will be available to the applet. Authors should use
this feature with extreme caution. An applet should be stopped before it is
serialized.</p>

<p>Either <a href="objects.html#adef-code" class="noxref"><samp class="ainst">
code</samp></a> or <a href="objects.html#adef-object" class="noxref"><samp
class="ainst">object</samp></a> must be present. If both <a href=
"objects.html#adef-code" class="noxref"><samp class="ainst">code</samp></a> and
<a href="objects.html#adef-object" class="noxref"><samp class="ainst">
object</samp></a> are given, it is an error if they provide different class
names.</p>
</dd>

<dt><a name="adef-width-APPLET"><samp class="adef">width</samp></a> = <a href=
"../types.html#type-length"><em>length</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the initial width of the applet's display area
(excluding any windows or dialogs that the applet creates).</dd>

<dt><a name="adef-height-APPLET"><samp class="adef">height</samp></a> = <a
href="../types.html#type-length"><em>length</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute specifies the initial height of the applet's display area
(excluding any windows or dialogs that the applet creates).</dd>
</dl>
</div>

<div class="aref-list">
<p><em>Attributes defined elsewhere</em></p>

<ul>
<li><a href="global.html#adef-id" class="noxref"><samp class="ainst">
id</samp></a>, <a href="global.html#adef-class" class="noxref"><samp class=
"ainst">class</samp></a> (<a href=
"../struct/global.html#id-and-class">document-wide identifiers</a>)</li>

<li><a href="global.html#adef-title" class="noxref"><samp class="ainst">
title</samp></a> (<a href="../struct/global.html#title">element title</a>)</li>

<li><a href="../present/styles.html#adef-style" class="noxref"><samp class=
"ainst">style</samp></a> (<a href="../present/styles.html#style-element">inline
style information</a>)</li>

<li><a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> (<a href="#alternate-text">alternate text</a>)</li>

<li><a href="objects.html#adef-align-IMG" class="noxref"><samp class=
"ainst-IMG">align</samp></a>, <a href="objects.html#adef-hspace" class=
"noxref"><samp class="ainst">hspace</samp></a>, <a href=
"objects.html#adef-vspace" class="noxref"><samp class="ainst">vspace</samp></a>
(<a href="#visual">visual presentation of objects, images, and
applets</a>)</li>
</ul>
</div>

<p>This element, supported by all Java-enabled browsers, allows designers to
embed a Java applet in an HTML document. It has been <a href=
"../conform.html#deprecated">deprecated</a> in favor of the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element.</p>

<p>The content of the <a href="objects.html#edef-APPLET" class="noxref"><samp
class="einst">APPLET</samp></a> acts as alternate information for user agents
that don't support this element or are currently configured not to support
applets. User agents must ignore the content otherwise.</p>

<div class="deprecated-example">
<p><span class="example-title">DEPRECATED EXAMPLE:</span>
<br>
In the following example, the <a href="objects.html#edef-APPLET" class=
"noxref"><samp class="einst">APPLET</samp></a> element includes a Java applet
in the document. Since no <a href="objects.html#adef-codebase-APPLET" class=
"noxref"><samp class="ainst-APPLET">codebase</samp></a> is supplied, the applet
is assumed to be in the same directory as the current document.</p>

<pre>
&lt;APPLET code="Bubbles.class" width="500" height="500"&gt;
Java applet that draws animated bubbles.
&lt;/APPLET&gt;
</pre>
</div>

<div class="example">
<p>This example may be rewritten with <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a> as follows:</p>

<pre>
&lt;P&gt;&lt;OBJECT codetype="application/java"
        classid="java:Bubbles.class"
        width="500" height="500"&gt;
Java applet that draws animated bubbles.
&lt;/OBJECT&gt;
</pre>
</div>

<p>Initial values may be supplied to the applet via the <a href=
"objects.html#edef-PARAM" class="noxref"><samp class="einst">PARAM</samp></a>
element.</p>

<div class="deprecated-example">
<p><span class="example-title">DEPRECATED EXAMPLE:</span>
<br>
The following sample Java applet:</p>

<pre>
&lt;APPLET code="AudioItem" width="15" height="15"&gt;
&lt;PARAM name="snd" value="Hello.au|Welcome.au"&gt;
Java applet that plays a welcoming sound.
&lt;/APPLET&gt;
</pre>

<p>may be rewritten as follows with <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a>:</p>

<pre>
&lt;OBJECT codetype="application/java"
        classid="AudioItem"
        width="15" height="15"&gt;
&lt;PARAM name="snd" value="Hello.au|Welcome.au"&gt;
Java applet that plays a welcoming sound.
&lt;/OBJECT&gt;
</pre>
</div>

<h2><a name="h-13.5">13.5</a> <a name="embedded-documents">Notes on embedded
documents</a></h2>

Sometimes, rather than <a href="links.html">linking</a> to a document, an
author may want to embed it directly into a primary HTML document. Authors may
use either the <a href="../present/frames.html#edef-IFRAME" class="noxref">
<samp class="einst">IFRAME</samp></a> element or the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element for this purpose, but the elements differ in some ways. Not only do the
two elements have different content models, the <a href=
"../present/frames.html#edef-IFRAME" class="noxref"><samp class="einst">
IFRAME</samp></a> element may be a target frame (see the section on <a href=
"../present/frames.html#target-info">specifying target frame information</a>
for details) and may be "selected" by a user agent as the focus for printing,
viewing HTML source, etc. User agents may render selected frames elements in
ways that distinguish them from unselected frames (e.g., by drawing a border
around the selected frame).

<p><span class="index-inst" title="document::ways to embed"><a name=
"idx-document-1">An embedded document</a></span> is entirely independent of the
document in which it is embedded. For instance, relative URIs within the
embedded document <a href="links.html#resolving-relative-uris">resolve</a>
according to the base URI of the embedded document, not that of the main
document. An embedded document is only rendered within another document (e.g.,
in a subwindow); it remains otherwise independent.</p>

<div class="example">
<p>For instance, the following line embeds the contents of <tt>
embed_me.html</tt> at the location where the <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a> definition occurs.</p>

<pre>
<em>...text before...</em>
&lt;OBJECT data="embed_me.html"&gt;
Warning: embed_me.html could not be embedded.
&lt;/OBJECT&gt;
<em>...text after...</em>
</pre>

<p>Recall that the contents of <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a> must only be rendered if the
file specified by the <a href="objects.html#adef-data" class="noxref"><samp
class="ainst">data</samp></a> attribute cannot be loaded.</p>
</div>

<p>The behavior of a user agent in cases where a file includes itself is not
defined.</p>

<h2><a name="h-13.6">13.6</a> <span class="index-def" title="image map"><a
name="include-maps">Image maps</a></span></h2>

Image maps allow authors to specify regions of an image or object and assign a
specific action to each region (e.g., retrieve a document, run a program, etc.)
When the region is activated by the user, the action is executed.

<p>An image map is created by associating an object with a specification of
sensitive geometric areas on the object.</p>

<p>There are two types of image maps:</p>

<ul>
<li><span class="index-def" title="client-side image map|image
map::client-side"><a name="didx-client-side_image_map"><dfn><em>
Client-side.</em></dfn></a></span> When a user activates a region of a
client-side image map with a mouse, the pixel coordinates are interpreted by
the user agent. The user agent selects a link that was specified for the
activated region and follows it.</li>

<li><span class="index-def" title="server-side image map|image
map::server-side"><a name="didx-server-side_image_map"><dfn><em>
Server-side.</em></dfn></a></span> When a user activates a region of a
server-side image map with a mouse, the pixel coordinates of the click are sent
to the server-side agent specified by the <a href="links.html#adef-href" class=
"noxref"><samp class="ainst">href</samp></a> attribute of the <a href=
"links.html#edef-A" class="noxref"><samp class="einst">A</samp></a> element.
The server-side agent interprets the coordinates and performs some action.</li>
</ul>

<p><span class="index-inst" title="accessibility::of image maps"><a name=
"idx-accessibility-2">Client-side image maps are preferred</a></span> over
server-side image maps for at least two reasons: they are accessible to people
browsing with non-graphical user agents and they offer immediate feedback as to
whether or not the pointer is over an active region.</p>

<h3><a name="h-13.6.1">13.6.1</a> <a name="client-side-maps">Client-side image
maps:</a> the <a name="edef-MAP"><samp class="edef">MAP</samp></a> and <a name=
"edef-AREA"><samp class="edef">AREA</samp></a> elements</h3>

<div class="dtd-fragment">
<pre class="dtd-fragment">
&lt;!ELEMENT <a href="objects.html#edef-MAP" class="noxref"><samp class=
"einst">MAP</samp></a> - - ((<a href=
"../sgml/dtd.html#block">%block;</a>) | AREA)+ -- client-side image map --&gt;
&lt;!ATTLIST MAP
  <a href=
"../sgml/dtd.html#attrs">%attrs;</a>                              -- <a href=
"../sgml/dtd.html#coreattrs">%coreattrs</a>, <a href=
"../sgml/dtd.html#i18n">%i18n</a>, <a href=
"../sgml/dtd.html#events">%events</a> --
  <a href="objects.html#adef-name-MAP" class="noxref"><samp class=
"ainst-MAP">name</samp></a>        <a href=
"../types.html#type-cdata">CDATA</a>          #REQUIRED -- for reference by usemap --
  &gt;
</pre>
</div>

<p><em>Start tag: <strong>required</strong>, End tag: <strong>
required</strong></em></p>

<div class="dtd-fragment">
<pre class="dtd-fragment">
&lt;!ELEMENT <a href="objects.html#edef-AREA" class="noxref"><samp class=
"einst">AREA</samp></a> - O EMPTY               -- client-side image map area --&gt;
&lt;!ATTLIST AREA
  <a href=
"../sgml/dtd.html#attrs">%attrs;</a>                              -- <a href=
"../sgml/dtd.html#coreattrs">%coreattrs</a>, <a href=
"../sgml/dtd.html#i18n">%i18n</a>, <a href=
"../sgml/dtd.html#events">%events</a> --
  <a href="objects.html#adef-shape" class="noxref"><samp class=
"ainst-AREA">shape</samp></a>       <a href=
"../sgml/dtd.html#Shape">%Shape;</a>        rect      -- controls interpretation of coords --
  <a href="objects.html#adef-coords" class="noxref"><samp class=
"ainst-AREA">coords</samp></a>      <a href=
"../sgml/dtd.html#Coords">%Coords;</a>       #IMPLIED  -- comma-separated list of lengths --
  <a href="links.html#adef-href" class="noxref"><samp class=
"ainst-AREA">href</samp></a>        <a href=
"../sgml/dtd.html#URI">%URI;</a>          #IMPLIED  -- URI for linked resource --
  <a href="objects.html#adef-nohref" class="noxref"><samp class=
"ainst-AREA">nohref</samp></a>      (nohref)       #IMPLIED  -- this region has no action --
  <a href="objects.html#adef-alt" class="noxref"><samp class=
"ainst-AREA">alt</samp></a>         <a href=
"../sgml/dtd.html#Text">%Text;</a>         #REQUIRED -- short description --
  <a href="../interact/forms.html#adef-tabindex" class="noxref"><samp class=
"ainst-AREA">tabindex</samp></a>    <a href=
"../types.html#type-number">NUMBER</a>         #IMPLIED  -- position in tabbing order --
  <a href="../interact/forms.html#adef-accesskey" class="noxref"><samp class=
"ainst-AREA">accesskey</samp></a>   <a href=
"../sgml/dtd.html#Character">%Character;</a>    #IMPLIED  -- accessibility key character --
  <a href="../interact/scripts.html#adef-onfocus" class="noxref"><samp class=
"ainst-AREA">onfocus</samp></a>     <a href=
"../sgml/dtd.html#Script">%Script;</a>       #IMPLIED  -- the element got the focus --
  <a href="../interact/scripts.html#adef-onblur" class="noxref"><samp class=
"ainst-AREA">onblur</samp></a>      <a href=
"../sgml/dtd.html#Script">%Script;</a>       #IMPLIED  -- the element lost the focus --
  &gt;
</pre>
</div>

<p><em>Start tag: <strong>required</strong>, End tag: <strong>
forbidden</strong></em></p>

<div class="adef-list">
<p><em>MAP attribute definitions</em></p>

<dl>
<dt><a name="adef-name-MAP"><samp class="adef">name</samp></a> = <a href=
"../types.html#type-cdata"><em>cdata</em></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>This attribute assigns a name to the image map defined by a <a href=
"objects.html#edef-MAP" class="noxref"><samp class="einst">MAP</samp></a>
element.</dd>
</dl>
</div>

<div class="adef-list">
<p><em>AREA attribute definitions</em></p>

<dl>
<dt><a name="adef-shape"><samp class="adef">shape</samp></a> = <samp>
default|rect|circle|poly</samp> <a href="../types.html#case-insensitive">
[CI]</a></dt>

<dd>This attribute specifies the shape of a region. Possible values:

<ul>
<li><samp>default:</samp> Specifies the entire region.</li>

<li><samp>rect:</samp> Define a rectangular region.</li>

<li><samp>circle:</samp> Define a circular region.</li>

<li><samp>poly:</samp> Define a polygonal region.</li>
</ul>
</dd>

<dt><a name="adef-coords"><samp class="adef">coords</samp></a> = <em>
coordinates</em> <a href="../types.html#case-neutral">[CN]</a></dt>

<dd>This attribute specifies the position and shape on the screen. The number
and order of values depends on the shape being defined. Possible combinations:

<ul>
<li><samp>rect:</samp> left-x, top-y, right-x, bottom-y.</li>

<li><samp>circle:</samp> center-x, center-y, radius. <strong>Note.</strong>
When the radius value is a percentage value, user agents should calculate the
final radius value based on the associated object's width and height. The
radius should be the smaller value of the two.</li>

<li><samp>poly:</samp> x1, y1, x2, y2, ..., xN, yN. The first x and y
coordinate pair and the last should be the same to close the polygon. When
these coordinate values are not the same, user agents should infer an
additional coordinate pair to close the polygon.</li>
</ul>

<p>Coordinates are relative to the top, left corner of the object. All values
are <a href="../types.html#type-length">lengths</a>. All values are separated
by commas.</p>
</dd>

<dt><a name="adef-nohref"><samp class="adef">nohref</samp></a> <a href=
"../types.html#case-insensitive">[CI]</a></dt>

<dd>When set, this boolean attribute specifies that a region has no associated
link.</dd>
</dl>
</div>

<div class="adef-list">
<p><em>Attribute to associate an image map with an element</em></p>

<dl>
<dt><a name="adef-usemap"><samp class="adef">usemap</samp></a> = <a href=
"../types.html#type-uri"><em>uri</em></a> <a href=
"../types.html#see-type-for-case">[CT]</a></dt>

<dd>This attribute associates an image map with an element. The image map is
defined by a <a href="objects.html#edef-MAP" class="noxref"><samp class=
"einst">MAP</samp></a> element. The value of <samp>usemap</samp> must match the
value of the <a href="objects.html#adef-name-MAP" class="noxref"><samp class=
"ainst-MAP">name</samp></a> attribute of the associated <a href=
"objects.html#edef-MAP" class="noxref"><samp class="einst">MAP</samp></a>
element.</dd>
</dl>
</div>

<div class="aref-list">
<p><em>Attributes defined elsewhere</em></p>

<ul>
<li><a href="global.html#adef-id" class="noxref"><samp class="ainst">
id</samp></a>, <a href="global.html#adef-class" class="noxref"><samp class=
"ainst">class</samp></a> (<a href=
"../struct/global.html#id-and-class">document-wide identifiers</a>)</li>

<li><a href="dirlang.html#adef-lang" class="noxref"><samp class="ainst">
lang</samp></a> (<a href="../struct/dirlang.html#language-info">language
information</a>), <a href="dirlang.html#adef-dir" class="noxref"><samp class=
"ainst">dir</samp></a> (<a href="../struct/dirlang.html#bidirection">text
direction</a>)</li>

<li><a href="global.html#adef-title" class="noxref"><samp class="ainst">
title</samp></a> (<a href="../struct/global.html#title">element title</a>)</li>

<li><a href="../present/styles.html#adef-style" class="noxref"><samp class=
"ainst">style</samp></a> (<a href="../present/styles.html#style-element">inline
style information</a>)</li>

<li><a href="../interact/forms.html#adef-name-INPUT" class="noxref"><samp
class="ainst-INPUT">name</samp></a> (<a href=
"../interact/forms.html#submit-format">submitting objects with forms</a>)</li>

<li><a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> (<a href="#alternate-text">alternate text</a>)</li>

<li><a href="links.html#adef-href" class="noxref"><samp class="ainst">
href</samp></a> (<a href="links.html#edef-A">anchor reference</a>) <a href=
"../present/frames.html#adef-target" class="noxref"><samp class="ainst">
target</samp></a> (<a href="../present/frames.html#target-info">frame target
information</a>)</li>

<li><a href="../interact/forms.html#adef-tabindex" class="noxref"><samp class=
"ainst">tabindex</samp></a> (<a href=
"../interact/forms.html#tabbing-navigation">tabbing navigation</a>)</li>

<li><a href="../interact/forms.html#adef-accesskey" class="noxref"><samp class=
"ainst">accesskey</samp></a> (<a href=
"../interact/forms.html#access-keys">access keys</a>)</li>

<li><a href="objects.html#adef-shape" class="noxref"><samp class="ainst">
shape</samp></a> (<a href="#include-maps">image maps</a>)</li>

<li><a href="../interact/scripts.html#adef-onclick" class="noxref"><samp class=
"ainst">onclick</samp></a>, <a href="../interact/scripts.html#adef-ondblclick"
class="noxref"><samp class="ainst">ondblclick</samp></a>, <a href=
"../interact/scripts.html#adef-onmousedown" class="noxref"><samp class="ainst">
onmousedown</samp></a>, <a href="../interact/scripts.html#adef-onmouseup"
class="noxref"><samp class="ainst">onmouseup</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseover" class="noxref"><samp class="ainst">
onmouseover</samp></a>, <a href="../interact/scripts.html#adef-onmousemove"
class="noxref"><samp class="ainst">onmousemove</samp></a>, <a href=
"../interact/scripts.html#adef-onmouseout" class="noxref"><samp class="ainst">
onmouseout</samp></a>, <a href="../interact/scripts.html#adef-onkeypress"
class="noxref"><samp class="ainst">onkeypress</samp></a>, <a href=
"../interact/scripts.html#adef-onkeydown" class="noxref"><samp class="ainst">
onkeydown</samp></a>, <a href="../interact/scripts.html#adef-onkeyup" class=
"noxref"><samp class="ainst">onkeyup</samp></a>, <a href=
"../interact/scripts.html#adef-onfocus" class="noxref"><samp class="ainst">
onfocus</samp></a>, <a href="../interact/scripts.html#adef-onblur" class=
"noxref"><samp class="ainst">onblur</samp></a> (<a href=
"../interact/scripts.html#events">intrinsic events</a>)</li>
</ul>
</div>

<p>The <a href="objects.html#edef-MAP" class="noxref"><samp class="einst">
MAP</samp></a> element specifies a client-side image map (or other navigation
mechanism) that may be associated with another elements (<a href=
"objects.html#edef-IMG" class="noxref"><samp class="einst">IMG</samp></a>, <a
href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>, or <a href="../interact/forms.html#edef-INPUT" class=
"noxref"><samp class="einst">INPUT</samp></a>). An image map is associated with
an element via the element's <a href="objects.html#adef-usemap" class="noxref">
<samp class="ainst">usemap</samp></a> attribute. The <a href=
"objects.html#edef-MAP" class="noxref"><samp class="einst">MAP</samp></a>
element may be used without an associated image for general navigation
mechanisms.</p>

<p>The presence of the <a href="objects.html#adef-usemap" class="noxref"><samp
class="ainst">usemap</samp></a> attribute for an <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
implies that the object being included is an image. <span class="index-inst"
title="image map::with OBJECT|user agent::handling image maps"><a name=
"idx-image_map-3">Furthermore</a></span>, when the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element has an associated client-side image map, user agents may implement user
interaction with the <a href="objects.html#edef-OBJECT" class="noxref"><samp
class="einst">OBJECT</samp></a> solely in terms of the client-side image map.
This allows user agents (such as an audio browser or robot) to interact with
the <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> without having to process it; the user agent may even elect
not to retrieve (or process) the object. When an <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
has an associated image map, authors should not expect that the object will be
retrieved or processed by every user agent.</p>

<p><span class="index-inst" title="client-side image map::creation of">The <a
name="idx-client-side_image_map-1" href="objects.html#edef-MAP" class="noxref">
<samp class="einst">MAP</samp></a> element content model allows authors to
combine the following:</span></p>

<ol>
<li>One or more <a href="objects.html#edef-AREA" class="noxref"><samp class=
"einst">AREA</samp></a> elements. These elements have no content but specify
the geometric regions of the image map and the link associated with each
region. Note that user agents do not generally render <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
elements. Therefore, authors must provide alternate text for each <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
with the <a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> attribute (see below for information on <a href=
"#alternate-text">how to specify alternate text</a>).</li>

<li>Block-level content. This content should include <a href=
"links.html#edef-A" class="noxref"><samp class="einst">A</samp></a> elements
that specify the geometric regions of the image map and the link associated
with each region. Note that the user agent should render block-level content of
a <a href="objects.html#edef-MAP" class="noxref"><samp class="einst">
MAP</samp></a> element. Authors should use this method to create more
accessible documents.</li>
</ol>

<p>When a <a href="objects.html#edef-MAP" class="noxref"><samp class="einst">
MAP</samp></a> element contains mixed content (both <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
elements and block-level content), user agents must ignore the <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
elements.</p>

<p>Authors should specify an image maps's geometry completely with <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
elements, or completely with <a href="links.html#edef-A" class="noxref"><samp
class="einst">A</samp></a> elements, or completely with both if content is
mixed. Authors may wish to mix content so that older user agents will handle
map geometries specified by <a href="objects.html#edef-AREA" class="noxref">
<samp class="einst">AREA</samp></a> elements and new user agents will take
advantage of richer block content.</p>

<p><span class="index-inst" title="image map::overlapping regions of"><a name=
"idx-image_map-4">If two or more defined regions overlap,</a></span> the
region-defining element that appears earliest in the document takes precedence
(i.e., responds to user input).</p>

<p><span class="index-inst" title="accessibility::of image maps|image
map::accessibility of"><a name="idx-accessibility-3">User agents and authors
should offer textual alternates</a></span> to graphical image maps for cases
when graphics are not available or the user cannot access them. For example,
user agents may use <a href="objects.html#adef-alt" class="noxref"><samp class=
"ainst">alt</samp></a> text to create textual links in place of a graphical
image map. Such links may be activated in a variety of ways (keyboard, voice
activation, etc.).</p>

<div class="note">
<p><em><strong>Note.</strong> <a href="objects.html#edef-MAP" class="noxref">
<samp class="einst">MAP</samp></a> is not backwards compatible with HTML 2.0
user agents.</em></p>
</div>

<h4>Client-side image map examples<a name="h-13.6.1.1">&nbsp;</a></h4>

<div class="example">
<p>In the following example, we create a client-side image map for the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element. We do not want to render the image map's contents when the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
is rendered, so we "hide" the <a href="objects.html#edef-MAP" class="noxref">
<samp class="einst">MAP</samp></a> element within the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element's content. Consequently, the <a href="objects.html#edef-MAP" class=
"noxref"><samp class="einst">MAP</samp></a> element's contents will only be
rendered if the <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> cannot be rendered.</p>

<pre>
&lt;HTML&gt;
   &lt;HEAD&gt;
      &lt;TITLE&gt;The cool site!&lt;/TITLE&gt;
   &lt;/HEAD&gt;
   &lt;BODY&gt;
     &lt;P&gt;&lt;OBJECT data="navbar1.gif" type="image/gif" usemap="#map1"&gt;
     &lt;MAP name="map1"&gt;
       &lt;P&gt;Navigate the site:
       &lt;A href="guide.html" shape="rect" coords="0,0,118,28"&gt;Access Guide&lt;/a&gt; |
       &lt;A href="shortcut.html" shape="rect" coords="118,0,184,28"&gt;Go&lt;/A&gt; |
       &lt;A href="search.html" shape="circle" coords="184,200,60"&gt;Search&lt;/A&gt; |
       &lt;A href="top10.html" shape="poly" coords="276,0,276,28,100,200,50,50,276,0"&gt;Top Ten&lt;/A&gt;
     &lt;/MAP&gt;
     &lt;/OBJECT&gt;
   &lt;/BODY&gt;
&lt;/HTML&gt;
</pre>

<p>We may want to render the image map's contents even when a user agent can
render the <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a>. For instance, we may want to associate an image map
with an <a href="objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a> element <em>and</em> include a text navigation bar at the
bottom of the page. To do so, we define the <a href="objects.html#edef-MAP"
class="noxref"><samp class="einst">MAP</samp></a> element outside the <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">
OBJECT</samp></a>:</p>

<pre>
&lt;HTML&gt;
   &lt;HEAD&gt;
      &lt;TITLE&gt;The cool site!&lt;/TITLE&gt;
   &lt;/HEAD&gt;
   &lt;BODY&gt;
     &lt;P&gt;&lt;OBJECT data="navbar1.gif" type="image/gif" usemap="#map1"&gt;
     &lt;/OBJECT&gt;

     <em>...the rest of the page here...</em>

     &lt;MAP name="map1"&gt;
       &lt;P&gt;Navigate the site:
       &lt;A href="guide.html" shape="rect" coords="0,0,118,28"&gt;Access Guide&lt;/a&gt; |
       &lt;A href="shortcut.html" shape="rect" coords="118,0,184,28"&gt;Go&lt;/A&gt; |
       &lt;A href="search.html" shape="circle" coords="184,200,60"&gt;Search&lt;/A&gt; |
       &lt;A href="top10.html" shape="poly" coords="276,0,276,28,100,200,50,50,276,0"&gt;Top Ten&lt;/A&gt;
     &lt;/MAP&gt;
   &lt;/BODY&gt;
&lt;/HTML&gt;
</pre>
</div>

<div class="example">
<p>In the following example, we create a similar image map, this time using the
<a href="objects.html#edef-AREA" class="noxref"><samp class="einst">
AREA</samp></a> element. Note the use of <a href="objects.html#adef-alt" class=
"noxref"><samp class="ainst">alt</samp></a> text:</p>

<pre>
&lt;P&gt;&lt;OBJECT data="navbar1.gif" type="image/gif" usemap="#map1"&gt;
   &lt;P&gt;This is a navigation bar.
   &lt;/OBJECT&gt;

&lt;MAP name="map1"&gt;
 &lt;AREA href="guide.html"
          alt="Access Guide"
          shape="rect"
          coords="0,0,118,28"&gt;
 &lt;AREA href="search.html"
          alt="Search"
          shape="rect"
          coords="184,0,276,28"&gt;
 &lt;AREA href="shortcut.html"
          alt="Go"
          shape="circle"
          coords="184,200,60"&gt;
 &lt;AREA href="top10.html"
          alt="Top Ten"
          shape="poly"
          coords="276,0,276,28,100,200,50,50,276,0"&gt;
&lt;/MAP&gt;
</pre>

<p>Here is a similar version using the <a href="objects.html#edef-IMG" class=
"noxref"><samp class="einst">IMG</samp></a> element instead of <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
(with the same <a href="objects.html#edef-MAP" class="noxref"><samp class=
"einst">MAP</samp></a> declaration):</p>

<pre>
&lt;P&gt;&lt;IMG src="navbar1.gif" usemap="#map1" alt="navigation bar"&gt;
</pre>
</div>

<div class="example">
<p>The following example illustrates how image maps may be shared.</p>

<p>Nested <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> elements are useful for providing fallbacks in case a
user agent doesn't support certain formats. For example:</p>

<pre>
&lt;P&gt;
&lt;OBJECT data="navbar.png" type="image/png"&gt;
  &lt;OBJECT data="navbar.gif" type="image/gif"&gt;
    <em>text describing the image...</em>
  &lt;/OBJECT&gt;
&lt;/OBJECT&gt;
</pre>

<p>If the user agent doesn't support the PNG format, it tries to render the GIF
image. If it doesn't support GIF (e.g., it's a speech-based user agent), it
defaults to the text description provided as the content of the inner <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
element. When <a href="objects.html#edef-OBJECT" class="noxref"><samp class=
"einst">OBJECT</samp></a> elements are nested this way, authors may share image
maps among them:</p>

<pre>
&lt;P&gt;
&lt;OBJECT data="navbar.png" type="image/png" usemap="#map1"&gt;
  &lt;OBJECT data="navbar.gif" type="image/gif" usemap="#map1"&gt;
     &lt;MAP name="map1"&gt;
     &lt;P&gt;Navigate the site:
      &lt;A href="guide.html" shape="rect" coords="0,0,118,28"&gt;Access Guide&lt;/a&gt; |
      &lt;A href="shortcut.html" shape="rect" coords="118,0,184,28"&gt;Go&lt;/A&gt; |
      &lt;A href="search.html" shape="circle" coords="184,200,60"&gt;Search&lt;/A&gt; |
      &lt;A href="top10.html" shape="poly" coords="276,0,276,28,100,200,50,50,276,0"&gt;Top Ten&lt;/A&gt;
     &lt;/MAP&gt;
  &lt;/OBJECT&gt;
&lt;/OBJECT&gt;
</pre>
</div>

<div class="example">
<p>The following example illustrates how anchors may be specified to create
inactive zones within an image map. The first anchor specifies a small circular
region with no associated link. The second anchor specifies a larger circular
region with the same center coordinates. Combined, the two form a ring whose
center is inactive and whose rim is active. The order of the anchor definitions
is important, since the smaller circle must override the larger circle.</p>

<pre>
&lt;MAP name="map1"&gt;
&lt;P&gt;
&lt;A shape="circle" coords="100,200,50"&gt;I'm inactive.&lt;/A&gt;
&lt;A href="outer-ring-link.html" shape="circle" coords="100,200,250"&gt;I'm active.&lt;/A&gt;
&lt;/MAP&gt;
</pre>
</div>

<p>Similarly, the <a href="objects.html#adef-nohref" class="noxref"><samp
class="ainst-AREA">nohref</samp></a> attribute for the <a href=
"objects.html#edef-AREA" class="noxref"><samp class="einst">AREA</samp></a>
element declares that geometric region has no associated link.</p>

<h3><a name="h-13.6.2">13.6.2</a> <span class="index-inst" title="image
map::server side|server-side image map"><a name="idx-image_map-6">Server-side
image maps</a></span></h3>

<p><a name="server-side">Server-side image maps</a> may be interesting in cases
where the image map is too complicated for a client-side image map.</p>

<p>It is only possible to define a server-side image map for the <a href=
"objects.html#edef-IMG" class="noxref"><samp class="einst">IMG</samp></a> and
<a href="../interact/forms.html#edef-INPUT" class="noxref"><samp class="einst">
INPUT</samp></a> elements. In the case of <a href="objects.html#edef-IMG"
class="noxref"><samp class="einst">IMG</samp></a>, the <a href=
"objects.html#edef-IMG" class="noxref"><samp class="einst">IMG</samp></a> must
be inside an <a href="links.html#edef-A" class="noxref"><samp class="einst">
A</samp></a> element and the boolean attribute <a name="adef-ismap"><samp
class="adef">ismap</samp></a> (<a href=
"../types.html#case-insensitive">[CI]</a>) must be set. In the case of <a href=
"../interact/forms.html#edef-INPUT" class="noxref"><samp class="einst">
INPUT</samp></a>, the <a href="../interact/forms.html#edef-INPUT" class=
"noxref"><samp class="einst">INPUT</samp></a> must be of type "image".</p>

<p>When the user activates the link by clicking on the image, the screen
coordinates are sent directly to the server where the document resides. Screen
coordinates are expressed as screen pixel values relative to the image. For
normative information about the definition of a pixel and how to scale it,
please consult <a rel="biblioentry" href="../references.html#ref-CSS1" class=
"normref">[CSS1]</a>.</p>

<div class="example">
<p>In the following example, the active region defines a server-side link.
Thus, a click anywhere on the image will cause the click's coordinates to be
sent to the server.</p>

<pre>
&lt;P&gt;&lt;A href="http://www.acme.com/cgi-bin/competition"&gt;
        &lt;IMG src="game.gif" ismap alt="target"&gt;&lt;/A&gt;
</pre>
</div>

<p><span class="index-inst" title="coordinates::of server-side image map| image
map|server-side image map::click coordinates"><a name="idx-coordinates">The
location clicked</a></span> is passed to the server as follows. The user agent
derives a new URI from the URI specified by the <a href="links.html#adef-href"
class="noxref"><samp class="ainst">href</samp></a> attribute of the <a href=
"links.html#edef-A" class="noxref"><samp class="einst">A</samp></a> element, by
appending `?' followed by the x and y coordinates, separated by a comma. The
link is then followed using the new URI. For instance, in the given example, if
the user clicks at the location x=10, y=27 then the derived URI is
"http://www.acme.com/cgi-bin/competition?10,27".</p>

<p>User agents that do not offer the user a means to select specific
coordinates (e.g., non-graphical user agents that rely on keyboard input,
speech-based user agents, etc.) should send the coordinates "0,0" to the server
when the link is activated.</p>

<h2><a name="h-13.7">13.7</a> <span class="index-inst" title="image::visual
rendering of|object::visual rendering of"><a name="visual">Visual presentation
of images, objects, and applets</a></span></h2>

<em>All <a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a> and <a href="objects.html#edef-OBJECT" class="noxref"><samp
class="einst">OBJECT</samp></a> attributes that concern visual alignment and
presentation have been <a href="../conform.html#deprecated">deprecated</a> in
favor of style sheets.</em>

<h3><a name="h-13.7.1">13.7.1</a> <span class="index-inst" title="image::width
and height of|object::width and height of"><a name="img-wh">Width and
height</a></span></h3>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-width-IMG"><samp class="adef">width</samp></a> = <a href=
"../types.html#type-length"><em>length</em></a> <a href=
"../types.html#case-neutral">[CN]</a></dt>

<dd>Image and object width override.</dd>

<dt><a name="adef-height-IMG"><samp class="adef">height</samp></a> = <a href=
"../types.html#type-length"><em>length</em></a> <a href=
"../types.html#case-neutral">[CN]</a></dt>

<dd>Image and object height override.</dd>
</dl>
</div>

<p>When specified, the <a href="objects.html#adef-width-IMG" class="noxref">
<samp class="ainst-IMG">width</samp></a> and <a href=
"objects.html#adef-height-IMG" class="noxref"><samp class="ainst-IMG">
height</samp></a> attributes tell user agents to override the natural image or
object size in favor of these values.</p>

<p>When the object is an image, it is scaled. User agents should do their best
to scale an object or image to match the width and height specified by the
author. Note that lengths expressed as percentages are based on the horizontal
or vertical space currently available, not on the natural size of the image,
object, or applet.</p>

<p>The <a href="objects.html#adef-height-IMG" class="noxref"><samp class=
"ainst-IMG">height</samp></a> and <a href="objects.html#adef-width-IMG" class=
"noxref"><samp class="ainst-IMG">width</samp></a> attributes give user agents
an idea of the size of an image or object so that they may reserve space for it
and continue rendering the document while waiting for the image data.</p>

<h3><a name="h-13.7.2">13.7.2</a> <span class="index-inst" title="white
space::around images and objects|image::white space around|object::white space
around"><a name="idx-white_space">White space around images and
objects</a></span></h3>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-hspace"><samp class="adef">hspace</samp></a> = <a href=
"../types.html#type-pixels"><em>pixels</em></a> <a href=
"../types.html#case-neutral">[CN]</a></dt>

<dd><a href="../conform.html#deprecated"><strong>Deprecated.</strong></a> This
attribute specifies the amount of white space to be inserted to the left and
right of an <a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a>, <a href="objects.html#edef-APPLET" class="noxref"><samp class=
"einst">APPLET</samp></a>, or <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a>. The default value is not
specified, but is generally a small, non-zero length.</dd>

<dt><a name="adef-vspace"><samp class="adef">vspace</samp></a> = <a href=
"../types.html#type-pixels"><em>pixels</em></a> <a href=
"../types.html#case-neutral">[CN]</a></dt>

<dd><a href="../conform.html#deprecated"><strong>Deprecated.</strong></a> This
attribute specifies the amount of white space to be inserted above and below an
<a href="objects.html#edef-IMG" class="noxref"><samp class="einst">
IMG</samp></a>, <a href="objects.html#edef-APPLET" class="noxref"><samp class=
"einst">APPLET</samp></a>, or <a href="objects.html#edef-OBJECT" class=
"noxref"><samp class="einst">OBJECT</samp></a>. The default value is not
specified, but is generally a small, non-zero length.</dd>
</dl>
</div>

<h3><a name="h-13.7.3">13.7.3</a> <span class="index-inst" title=
"border::around image|border::around object|image::border around|object::border
around"><a name="idx-border">Borders</a></span></h3>

<p>An image or object may be surrounded by a border (e.g., when a border is
specified by the user or when the image is the content of an <a href=
"links.html#edef-A" class="noxref"><samp class="einst">A</samp></a>
element).</p>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-border-IMG"><samp class="adef">border</samp></a> = <a href=
"../types.html#type-pixels"><em>pixels</em></a> <a href=
"../types.html#case-neutral">[CN]</a></dt>

<dd><a href="../conform.html#deprecated"><strong>Deprecated.</strong></a> This
attribute specifies the width of an <a href="objects.html#edef-IMG" class=
"noxref"><samp class="einst">IMG</samp></a> or <a href=
"objects.html#edef-OBJECT" class="noxref"><samp class="einst">OBJECT</samp></a>
border, in pixels. The default value for this attribute depends on the user
agent.</dd>
</dl>
</div>

<h3><a name="h-13.7.4">13.7.4</a> <span class="index-inst" title="alignment::of
images|alignment::of objects|object::alignment of|image::alignment of"><a name=
"alignment">Alignment</a></span></h3>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-align-IMG"><samp class="adef">align</samp></a> = <samp>
bottom|middle|top|left|right</samp></dt>

<dd><a href="../conform.html#deprecated"><strong>Deprecated.</strong></a> This
attribute specifies the position of an <a href="objects.html#edef-IMG" class=
"noxref"><samp class="einst">IMG</samp></a>, <a href="objects.html#edef-OBJECT"
class="noxref"><samp class="einst">OBJECT</samp></a>, or <a href=
"objects.html#edef-APPLET" class="noxref"><samp class="einst">APPLET</samp></a>
with respect to its context.</dd>
</dl>
</div>

<p>The following values for <a href="objects.html#adef-align-IMG" class=
"noxref"><samp class="ainst-IMG">align</samp></a> concern the object's position
with respect to surrounding text:</p>

<ul>
<li><samp>bottom:</samp> means that the bottom of the object should be
vertically aligned with the current baseline. This is the default value.</li>

<li><samp>middle:</samp> means that the center of the object should be
vertically aligned with the current baseline.</li>

<li><samp>top:</samp> means that the top of the object should be vertically
aligned with the top of the current text line.</li>
</ul>

<p>Two other values, <samp>left</samp> and <samp>right</samp>, cause the image
to float to the current left or right margin. They are discussed in the section
on <a href="../present/graphics.html#floating">floating objects</a>.</p>

<div class="note">
<p><em><strong>Differing interpretations of align.</strong> User agents vary in
their interpretation of the <a href="objects.html#adef-align-IMG" class=
"noxref"><samp class="ainst-IMG">align</samp></a> attribute. Some only take
into account what has occurred on the text line prior to the element, some take
into account the text on both sides of the element.</em></p>
</div>

<h2><a name="h-13.8">13.8</a> <span class="index-inst" title="alternate
text::specifying|accessibility::alternate text"><a name="alternate-text">How to
specify alternate text</a></span></h2>

<div class="adef-list">
<p><em>Attribute definitions</em></p>

<dl>
<dt><a name="adef-alt"><samp class="adef">alt</samp></a> = <a href=
"../types.html#type-text"><em>text</em></a> <a href=
"../types.html#case-sensitive">[CS]</a></dt>

<dd>For user agents that cannot display images, forms, or applets, this
attribute specifies alternate text. The language of the alternate text is
specified by the <a href="dirlang.html#adef-lang" class="noxref"><samp class=
"ainst">lang</samp></a> attribute.</dd>
</dl>
</div>

<p>Several non-textual elements (<a href="objects.html#edef-IMG" class=
"noxref"><samp class="einst">IMG</samp></a>, <a href="objects.html#edef-AREA"
class="noxref"><samp class="einst">AREA</samp></a>, <a href=
"objects.html#edef-APPLET" class="noxref"><samp class="einst">
APPLET</samp></a>, and <a href="../interact/forms.html#edef-INPUT" class=
"noxref"><samp class="einst">INPUT</samp></a>) let authors specify alternate
text to serve as content when the element cannot be rendered normally.
Specifying alternate text assists users without graphic display terminals,
users whose browsers don't support forms, visually impaired users, those who
use speech synthesizers, those who have configured their graphical user agents
not to display images, etc.</p>

<p>The <a href="objects.html#adef-alt" class="noxref"><samp class="ainst">
alt</samp></a> attribute must be specified for the <a href=
"objects.html#edef-IMG" class="noxref"><samp class="einst">IMG</samp></a> and
<a href="objects.html#edef-AREA" class="noxref"><samp class="einst">
AREA</samp></a> elements. It is optional for the <a href=
"../interact/forms.html#edef-INPUT" class="noxref"><samp class="einst">
INPUT</samp></a> and <a href="objects.html#edef-APPLET" class="noxref"><samp
class="einst">APPLET</samp></a> elements.</p>

<p>While alternate text may be very helpful, it must be handled with care.
Authors should observe the following guidelines:</p>

<ul>
<li>Do not specify irrelevant alternate text when including images intended to
<em>format</em> a page, for instance, <samp>alt="red ball"</samp> would be
inappropriate for an image that adds a red ball for decorating a heading or
paragraph. In such cases, the alternate text should be the empty string ("").
Authors are in any case advised to avoid using images to format pages; style
sheets should be used instead.</li>

<li>Do not specify meaningless alternate text (e.g., "dummy text"). Not only
will this frustrate users, it will slow down user agents that must convert text
to speech or braille output.</li>
</ul>

<p>Implementors should consult the section on <a href=
"../appendix/notes.html#accessibility">accessibility</a> for information about
how to handle cases of omitted alternate text.</p>

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