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</style><link href="http://www.w3.org/StyleSheets/TR/W3C-WD" rel="stylesheet" type="text/css" charset="utf-8" /></head>
  <body style="display: inherit;"><div class="head"><p><a href="http://www.w3.org/"><img width="72" height="48" alt="W3C" src="http://www.w3.org/Icons/w3c_home" /></a></p><h1 id="title" class="title" property="dcterms:title">RDFa Lite 1.1</h1><h2 content="2011-12-08T05:00:00+0000" datatype="xsd:dateTime" property="dcterms:issued" id="w3c-working-draft-08-december-2011"><acronym title="World Wide Web Consortium">W3C</acronym> Working Draft 08 December 2011</h2><dl><dt>This version:</dt><dd><a href="http://www.w3.org/TR/2011/WD-rdfa-lite-20111208/">http://www.w3.org/TR/2011/WD-rdfa-lite-20111208/</a></dd><dt>Latest published version:</dt><dd><a href="http://www.w3.org/TR/rdfa-lite/">http://www.w3.org/TR/rdfa-lite/</a></dd><dt>Latest editor's draft:</dt><dd><a href="http://www.w3.org/2010/02/rdfa/sources/rdfa-lite/">http://www.w3.org/2010/02/rdfa/sources/rdfa-lite/</a></dd><dt>Editor:</dt><dd rel="bibo:editor"><span typeof="foaf:Person"><a href="http://digitalbazaar.com/" content="Manu Sporny" property="foaf:name" rel="foaf:homepage">Manu Sporny</a>, <a href="http://digitalbazaar.com/" rel="foaf:workplaceHomepage">Digital Bazaar, Inc.</a></span>
</dd>
</dl><p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright" rel="license">Copyright</a> © 2011 <span rel="dcterms:publisher"><span typeof="foaf:Organization"><a href="http://www.w3.org/" content="World Wide Web Consotrium" property="foaf:name" rel="foaf:homepage"><acronym title="World Wide Web Consortium">W3C</acronym></a><sup>®</sup></span></span> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>, <a href="http://www.ercim.eu/"><acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym></a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. <acronym title="World Wide Web Consortium">W3C</acronym> <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a> and <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> rules apply.</p><hr /></div>
    <div id="abstract" class="introductory section" property="dcterms:abstract" datatype="" typeof="bibo:Chapter" about="#abstract"><h2>Abstract</h2>
      <p>
RDFa Lite is a small subset of RDFa consisting of a few attributes that may
be applied to most simple to moderate structured data markup tasks. While it
is not a complete solution for advanced markup tasks, it does provide a good
entry point for beginners.
      </p>
    </div><div class="introductory section" id="sotd" typeof="bibo:Chapter" about="#sotd"><h2>Status of This Document</h2><p><em>This section describes the status of this document at the time of its publication. Other documents may supersede this document. A list of current <acronym title="World Wide Web Consortium">W3C</acronym> publications and the latest revision of this technical report can be found in the <a href="http://www.w3.org/TR/"><acronym title="World Wide Web Consortium">W3C</acronym> technical reports index</a> at http://www.w3.org/TR/.</em></p><p>This document was published by the <a href="http://www.w3.org/2010/02/rdfa/"><acronym title="World Wide Web Consortium">W3C</acronym> RDF Web Applications Working Group</a> as a First Public Working Draft. The purpose of this document is to provide an easy 15 minute introduction to RDFa that will resonate with most Web developers. This document is not intended to be a complete specification of RDFa 1.1. The complete specification of RDFa can be found in RDFa Core or one of the host languages for RDFa: XHTML+RDFa, SVG+RDFa, or HTML+RDFa.
    This document is intended to become a <acronym title="World Wide Web Consortium">W3C</acronym> Recommendation. If you wish to make comments regarding this document, please send them to <a href="mailto:public-rdfa-wg@w3.org">public-rdfa-wg@w3.org</a> (<a href="mailto:public-rdfa-wg-request@w3.org?subject=subscribe">subscribe</a>, <a href="http://lists.w3.org/Archives/Public/public-rdfa-wg/">archives</a>). All feedback is welcome.</p><p>Publication as a Working Draft does not imply endorsement by the <acronym title="World Wide Web Consortium">W3C</acronym> Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.</p><p>This document was produced by a group operating under the <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/">5 February 2004 <acronym title="World Wide Web Consortium">W3C</acronym> Patent Policy</a>. <acronym title="World Wide Web Consortium">W3C</acronym> maintains a <a rel="disclosure" href="http://www.w3.org/2004/01/pp-impl/44350/status">public list of any patent disclosures</a> made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#def-essential">Essential Claim(s)</a> must disclose the information in accordance with <a href="http://www.w3.org/Consortium/Patent-Policy-20040205/#sec-Disclosure">section 6 of the <acronym title="World Wide Web Consortium">W3C</acronym> Patent Policy</a>.</p></div><div id="toc" typeof="bibo:Chapter" about="#toc" class="section"><h2 class="introductory">Table of Contents</h2><ul class="toc"><li class="tocline"><a href="#introduction" class="tocxref"><span class="secno">1. </span>Introduction</a></li><li class="tocline"><a href="#the-attributes" class="tocxref"><span class="secno">2. </span>The Attributes</a><ul class="toc"><li class="tocline"><a href="#vocab--typeof-and-property" class="tocxref"><span class="secno">2.1 </span>vocab, typeof and property</a></li><li class="tocline"><a href="#about" class="tocxref"><span class="secno">2.2 </span>about</a></li><li class="tocline"><a href="#prefix" class="tocxref"><span class="secno">2.3 </span>prefix</a></li></ul></li><li class="tocline"><a href="#conformance" class="tocxref"><span class="secno">3. </span>Conformance</a><ul class="toc"><li class="tocline"><a href="#document-conformance" class="tocxref"><span class="secno">3.1 </span>Document Conformance</a></li><li class="tocline"><a href="#rdfa-processor-conformance" class="tocxref"><span class="secno">3.2 </span>RDFa Processor Conformance</a></li><li class="tocline"><a href="#user-agent-conformance" class="tocxref"><span class="secno">3.3 </span>User Agent Conformance</a></li></ul></li><li class="tocline"><a href="#references" class="tocxref"><span class="secno">A. </span>References</a><ul class="toc"><li class="tocline"><a href="#normative-references" class="tocxref"><span class="secno">A.1 </span>Normative references</a></li><li class="tocline"><a href="#informative-references" class="tocxref"><span class="secno">A.2 </span>Informative references</a></li></ul></li></ul></div>

    <div id="introduction" typeof="bibo:Chapter" about="#introduction" class="section">

<!-- OddPage -->
<h2><span class="secno">1. </span>Introduction</h2>
      <p>
The RDFa syntax [<cite><a class="bibref" rel="biblioentry" href="#bib-RDFA-CORE">RDFA-CORE</a></cite>] is often criticized as having too much
functionality, leaving first-time authors confused about the more advanced
features. This lighter version of RDFa helps authors easily jump into the
structured data world. The goal was to create a very minimal subset that will
work for 80% of the folks out there doing simple data markup.
      </p>
    </div>

    <div id="the-attributes" typeof="bibo:Chapter" about="#the-attributes" class="section">

<!-- OddPage -->
<h2><span class="secno">2. </span>The Attributes</h2>
      <p>
RDFa Lite consists of five simple attributes; <code>vocab</code>,
<code>typeof</code>, <code>property</code>, <code>about</code>, and
<code>prefix</code>. RDFa 1.1 Lite is completely upwards compatible with the
full set of RDFa 1.1 attributes. This means that if an author finds that
RDFa Lite isn't powerful enough, transitioning to the full version of RDFa is
just a matter of adding the more powerful RDFa attributes into the existing
RDFa Lite markup.
      </p>

      <div id="vocab--typeof-and-property" typeof="bibo:Chapter" about="#vocab--typeof-and-property" class="section">
        <h3><span class="secno">2.1 </span>vocab, typeof and property</h3>
        <p>
RDFa, like Microformats and Microdata, allow us to talk about <em>things</em>
on the Web. Typically when we talk about a thing, we use a particular
<strong>vocabulary</strong> to talk about it. So, if you wanted to talk about
People, the vocabulary that you would use would specify terms like
<em>name</em> and <em>telephone number</em>. When we want to mark up things on
the Web, we need to do something very similar, which is specify which
vocabulary that we are going to be using. Here is a simple example that
specifies a vocabulary that we intend to use to markup things in the paragraph:
        </p>
        <pre class="example">&lt;p <span style="color: #5b5; font-weight: bold;">vocab=&quot;http://schema.org/&quot;</span>&gt;
   My name is Manu Sporny and you can give me a ring via 1-800-555-0199.
&lt;/p&gt;</pre>
        <p>
As you will note above, we have specified that we're going to be using the
<strong>vocabulary</strong> that can be found at
<code>http://schema.org/</code>. This is a vocabulary that has been
released by major search engine companies to talk about common things on the
Web that Search Engines care about – things like People, Places, Reviews,
Recipes, and Events. Once we have specified the vocabulary, we need to specify
the <strong>type of</strong> the thing that we're talking about. In this
particular case we are talking about a Person, which can be marked up like so:
        </p>
        <pre class="example">&lt;p vocab=&quot;http://schema.org/&quot; <span style="color: #5b5; font-weight: bold;">typeof=&quot;Person&quot;</span>&gt;
   My name is Manu Sporny and you can give me a ring via 1-800-555-0199.
&lt;/p&gt;</pre>
        <p>
Now all we need to do is specify which <strong>properties</strong> of that
person we want to point out to the search engine. In the following example, we
mark up the person's name and phone number:
        </p>
        <pre class="example">&lt;p vocab=&quot;http://schema.org/&quot; typeof=&quot;Person&quot;&gt;
   My name is
   &lt;span <span style="color: #5b5; font-weight: bold;">property=&quot;name&quot;</span>&gt;Manu Sporny&lt;/span&gt;
   and you can give me a ring via
   &lt;span <span style="color: #5b5; font-weight: bold;">property=&quot;telephone&quot;</span>&gt;1-800-555-0199&lt;/span&gt;.
&lt;/p&gt;</pre>
        <p>
Now, when somebody types in “phone number for Manu Sporny” into a
search engine, the search engine can more reliably answer the question
directly, or point the person searching to a more relevant Web page.
        </p>
      </div>

      <div id="about" typeof="bibo:Chapter" about="#about" class="section">
        <h3><span class="secno">2.2 </span>about</h3>
        <p>
If you want Web authors to be able to talk <em>about</em> the things on your
page, you can identify the thing using a hash and a name. For example:
        </p>
        <pre class="example">&lt;p vocab=&quot;http://schema.org/&quot; <span style="color: #5b5; font-weight: bold;">about=&quot;#manu&quot;</span> typeof=&quot;Person&quot;&gt;
   My name is
   &lt;span property=&quot;name&quot;&gt;Manu Sporny&lt;/span&gt;
   and you can give me a ring via
   &lt;span property=&quot;telephone&quot;&gt;1-800-555-0199&lt;/span&gt;.
   &lt;img property=&quot;image&quot; src=&quot;http://manu.sporny.org/images/manu.png&quot; /&gt;
&lt;/p&gt;</pre>
        <p>
If we assume that the markup above can be found at
<code>http://example.org/people</code>, then the identifier for the thing is
the address, plus the value in the <code>about</code> attribute. Therefore, the
identifier for the thing on the page would be:
<code>http://example.org/people#manu</code>. This identifier is also useful if
you want to talk about the thing on another Web page. By identifying all things
on the Web using a unique Uniform Resource Locator (URL), we can start building
a Web of things. Companies building software for the Web can use this
Web of things to answer complex questions like: &quot;What is Manu Sporny's phone
number and what does he look like?&quot;.
        </p>
        <p class="issue">
The Working Group is considering replacing the @about attribute with @resource.
The details of the proposal are
<a href="http://www.w3.org/2010/02/rdfa/wiki/ResourceAbout">outlined in the wiki</a>.
The Working Group needs
feedback from Web authors and implementers in order to ensure that the
decision reflects something that would be helpful to authors. The change
would result in the example above being changed to the following:
        </p>

        <pre class="example">&lt;p vocab=&quot;http://schema.org/&quot; <span style="color: #5b5; font-weight: bold;">resource=&quot;#manu&quot;</span> typeof=&quot;Person&quot;&gt;
   My name is
   &lt;span property=&quot;name&quot;&gt;Manu Sporny&lt;/span&gt;
   and you can give me a ring via
   &lt;span property=&quot;telephone&quot;&gt;1-800-555-0199&lt;/span&gt;.
   &lt;img property=&quot;image&quot; src=&quot;http://manu.sporny.org/images/manu.png&quot; /&gt;
&lt;/p&gt;</pre>
      </div>

      <div id="prefix" typeof="bibo:Chapter" about="#prefix" class="section">
        <h3><span class="secno">2.3 </span>prefix</h3>
        <p>
In some cases, a vocabulary may not have all of the terms an author needs when
describing their <em>thing</em>. The last feature in RDFa 1.1 Lite that some
authors might need is the ability to specify more than one vocabulary. For
example, if we are describing a Person and we need to specify that they have a
favorite animal, we could do something like the following:
        </p>
        <pre class="example">&lt;p vocab=&quot;http://schema.org/&quot; <span style="color: #5b5; font-weight: bold;">prefix=&quot;ov: http://open.vocab.org/terms/&quot;</span> about=&quot;#manu&quot; typeof=&quot;Person&quot;&gt;
   My name is
   &lt;span property=&quot;name&quot;&gt;Manu Sporny&lt;/span&gt;
   and you can give me a ring via
   &lt;span property=&quot;telephone&quot;&gt;1-800-555-0199&lt;/span&gt;.
   &lt;img property=&quot;image&quot; src=&quot;http://manu.sporny.org/images/manu.png&quot; /&gt;
   My favorite animal is the &lt;a <span style="color: #5b5; font-weight: bold;">property=&quot;ov:preferredAnimal&quot;</span>&gt;Liger&lt;/a&gt;.
&lt;/p&gt;</pre>
        <p>
The example assigns a short-hand prefix to the Open Vocabulary
(<code>ov</code>) and uses that prefix to specify the
<code>preferredAnimal</code> vocabulary term. Since schema.org doesn't have
a clear way of expressing a favorite animal, the author instead depends on
this alternate vocabulary to get the job done.
        </p>
        <p>
RDFa 1.1 Lite also pre-defines a number of
<a href="http://www.w3.org/2011/rdfa-context/rdfa-1.1">useful and popular
prefixes</a>, such as <code>dc</code>, <code>foaf</code> and
<code>schema</code>. This ensures that even if authors forget to declare the
popular prefixes, that their structured data will continue to work.
        </p>
    </div>
  </div>

<div id="conformance" typeof="bibo:Chapter" about="#conformance" class="section">
<!-- OddPage -->
<h2><span class="secno">3. </span>Conformance</h2><p>As well as sections marked as non-normative, all authoring guidelines, diagrams, examples, and notes in this specification are non-normative. Everything else in this specification is normative.</p>
<p>The key words <em class="rfc2119" title="must">must</em>, <em class="rfc2119" title="must not">must not</em>, <em class="rfc2119" title="required">required</em>, <em class="rfc2119" title="should">should</em>, <em class="rfc2119" title="should not">should not</em>, <em class="rfc2119" title="recommended">recommended</em>, <em class="rfc2119" title="may">may</em>, and <em class="rfc2119" title="optional">optional</em> in this specification are to be interpreted as described in [<cite><a class="bibref" rel="biblioentry" href="#bib-RFC2119">RFC2119</a></cite>].</p>


<div id="document-conformance" typeof="bibo:Chapter" about="#document-conformance" class="section">
<h3><span class="secno">3.1 </span>Document Conformance</h3>

  <p>In order for a document to claim that it is a conforming HTML+RDFa Lite
  document, it <em class="rfc2119" title="must">must</em> provide the facilities described as mandatory in this
  section. The document conformance criteria are listed below, of which only
  a subset are mandatory:</p>

  <ul>
    <li>All Document Conformance requirements stated as mandatory for the
    HTML5 language in the HTML+RDFa 1.1 [<cite><a class="bibref" rel="biblioentry" href="#bib-HTML-RDFA">HTML-RDFA</a></cite>] specification
    <em class="rfc2119" title="must">must</em> be met.</li>

    <li>All HTML5 elements and attributes <em class="rfc2119" title="should">should</em> be used in a way that is
    conformant with [<cite><a class="bibref" rel="biblioentry" href="#bib-HTML5">HTML5</a></cite>]. All RDFa attributes <em class="rfc2119" title="should">should</em> be used in a way that
    is conformant with [<cite><a class="bibref" rel="biblioentry" href="#bib-HTML-RDFA">HTML-RDFA</a></cite>] and this document.</li>
  </ul>

<p>An example of a conforming RDFa Lite document:</p>

<pre title="Example of an HTML+RDFa Lite 1.1 document" class="example">&lt;html lang=&quot;en&quot;&gt;
  &lt;head&gt;
    &lt;title&gt;Example Document&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
    &lt;p&gt;This website is &lt;a href=&quot;http://example.org/&quot;&gt;example.org&lt;/a&gt;.&lt;/p&gt;
  &lt;/body&gt;
&lt;/html&gt;</pre>

</div>

<div id="rdfa-processor-conformance" typeof="bibo:Chapter" about="#rdfa-processor-conformance" class="section">
  <h3><span class="secno">3.2 </span>RDFa Processor Conformance</h3>

  <p>The RDFa Processor conformance criteria are listed below, all of
  which are mandatory:</p>
  <ul>
    <li>An RDFa Processor <em class="rfc2119" title="must">must</em> implement all of the mandatory features
    specified in the RDFa Processor Conformance section of the HTML+RDFa 1.1
    specification [<cite><a class="bibref" rel="biblioentry" href="#bib-HTML-RDFA">HTML-RDFA</a></cite>].</li>
  </ul>
</div>

<div id="user-agent-conformance" typeof="bibo:Chapter" about="#user-agent-conformance" class="section">
<h3><span class="secno">3.3 </span>User Agent Conformance</h3>

  <p>A User Agent is considered to be a type of RDFa Processor when the
  User Agent stores or processes RDFa attributes and their values. The
  reason there are separate <em>RDFa Processor Conformance</em> and a
  <em>User Agent Conformance</em> sections is because one can be a valid
  HTML5 RDFa Processor but not a valid HTML5 User Agent (for example, by only
  providing a very small subset of rendering functionality).
  </p>

  <p>The User Agent conformance criteria are listed below, all of which are
  mandatory:</p>

  <ul>
    <li>A User Agent <em class="rfc2119" title="must">must</em> conform to all requirements listed in the
    <span>Conformance Requirements</span> section of the HTML+RDFa
    [<cite><a class="bibref" rel="biblioentry" href="#bib-HTML-RDFA">HTML-RDFA</a></cite>] specification that relate to the HTML5 language.
    </li>
  </ul>

</div>

</div>


<div id="references" class="appendix section" typeof="bibo:Chapter" about="#references">
<!-- OddPage -->
<h2><span class="secno">A. </span>References</h2><div id="normative-references" typeof="bibo:Chapter" about="#normative-references" class="section"><h3><span class="secno">A.1 </span>Normative references</h3><dl class="bibliography" about=""><dt id="bib-HTML-RDFA">[HTML-RDFA]</dt><dd rel="dcterms:requires">Sporny, Manu et. al. <a href="http://www.w3.org/TR/rdfa-in-html/"><cite>RDFa in HTML</cite></a> 2010. W3C. URL: <a href="http://www.w3.org/TR/rdfa-in-html/">http://www.w3.org/TR/rdfa-in-html/</a>
</dd><dt id="bib-HTML5">[HTML5]</dt><dd rel="dcterms:requires">Ian Hickson; David Hyatt. <a href="http://www.w3.org/TR/html5"><cite>HTML5.</cite></a> 25 May 2011. W3C Working Draft. (Work in progress.) URL: <a href="http://www.w3.org/TR/html5">http://www.w3.org/TR/html5</a>
</dd><dt id="bib-RFC2119">[RFC2119]</dt><dd rel="dcterms:requires">S. Bradner. <a href="http://www.ietf.org/rfc/rfc2119.txt"><cite>Key words for use in RFCs to Indicate Requirement Levels.</cite></a> March 1997. Internet RFC 2119.  URL: <a href="http://www.ietf.org/rfc/rfc2119.txt">http://www.ietf.org/rfc/rfc2119.txt</a>
</dd></dl></div><div id="informative-references" typeof="bibo:Chapter" about="#informative-references" class="section"><h3><span class="secno">A.2 </span>Informative references</h3><dl class="bibliography" about=""><dt id="bib-RDFA-CORE">[RDFA-CORE]</dt><dd rel="dcterms:references">Shane McCarron; et al. <a href="http://www.w3.org/TR/2011/WD-rdfa-core-20110331"><cite>RDFa Core 1.1: Syntax and processing rules for embedding RDF through attributes.</cite></a> 31 March 2011. W3C Working Draft. URL: <a href="http://www.w3.org/TR/2011/WD-rdfa-core-20110331">http://www.w3.org/TR/2011/WD-rdfa-core-20110331</a>
</dd></dl></div></div></body></html>