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<div class="head">
<p><a href="http://www.w3.org/"><img height="48" width="72"
src="http://www.w3.org/Icons/w3c_home" alt="W3C" border="0" /></a></p>

<h1 id="title">RDF Vocabulary Description Language 1.0: RDF Schema</h1>

<h2 id="doctype">W3C Recommendation 10 February 2004</h2>




<dl>
  <dt>This Version:</dt>
    <dd><a href="http://www.w3.org/TR/2004/REC-rdf-schema-20040210/">http://www.w3.org/TR/2004/REC-rdf-schema-20040210/</a></dd>
  <dt>Latest Version:</dt>
    <dd><a
      href="http://www.w3.org/TR/rdf-schema/">http://www.w3.org/TR/rdf-schema/</a></dd>
  <dt>Previous Version:</dt>
    <dd><a
      href="http://www.w3.org/TR/2003/PR-rdf-schema-20031215/">http://www.w3.org/TR/2003/PR-rdf-schema-20031215/</a></dd>
  <dt>Editors:</dt>
    <dd><a href="http://www.w3.org/People/DanBri/">Dan Brickley</a>, W3C &lt;<a>danbri@w3.org</a>&gt;</dd>     <dd>R.V. Guha, IBM &lt;<a
      href="mailto:rguha@us.ibm.com">rguha@us.ibm.com</a>&gt;</dd>
  <dt>Series editor:</dt>
    <dd><a href="http://www-uk.hpl.hp.com/people/bwm/">Brian McBride</a>
      (Hewlett Packard Labs) &lt;<a
      href="mailto:bwm@hplb.hpl.hp.com">bwm@hplb.hpl.hp.com</a>&gt;</dd>
</dl>
			<a href="#ch_acknowledgments">Acknowledgments</a> 







<p>Please refer to the <a
href="http://www.w3.org/2001/sw/RDFCore/errata#rdf-schema"><strong>errata</strong></a>
for this document, which may include some normative corrections.</p>

<p>See also <a href="http://www.w3.org/2001/sw/RDFCore/translation/rdf-schema">translations</a>.</p>

<p class="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright"> Copyright</a>
 &#xa9; 2004 <a href="http://www.w3.org/"><acronym title="World Wide Web Consortium">W3C</acronym></a>
 <sup>&#xae;</sup> (<a href="http://www.csail.mit.edu/"><acronym title="Massachusetts Institute of Technology">MIT</acronym></a>,
  <a href="http://www.ercim.org/">
  <acronym title="European Research Consortium for Informatics and Mathematics">ERCIM</acronym>
  </a>, <a href="http://www.keio.ac.jp/">Keio</a>), All Rights Reserved. W3C 
  <a href="http://www.w3.org/Consortium/Legal/ipr-notice#Legal_Disclaimer">liability</a>, 
  <a href="http://www.w3.org/Consortium/Legal/ipr-notice#W3C_Trademarks">trademark</a>, 
  <a href="http://www.w3.org/Consortium/Legal/copyright-documents">document use</a> and 
  <a href="http://www.w3.org/Consortium/Legal/copyright-software">software licensing</a> rules apply.</p>


</div>
<hr />

<h2>Abstract</h2>

<p>The Resource Description Framework (RDF) is a general-purpose language for
representing information in the Web. This specification describes how to use
RDF to describe RDF vocabularies. This specification defines a vocabulary for
this purpose and defines other built-in RDF vocabulary initially specified in
the RDF Model and Syntax Specification.</p>

<div class="status">

<h2 class="nonum">
<a id="status" name="status">Status of this Document</a>
</h2>
<!-- Start Status-Of-This-Document Text -->

<p>This document has been reviewed by W3C Members and other interested
parties, and it has been endorsed by the Director as a <a
href="http://www.w3.org/2003/06/Process-20030618/tr.html#RecsW3C">W3C
Recommendation</a>.  W3C's role in making the Recommendation is to
draw attention to the specification and to promote its widespread
deployment. This enhances the functionality and interoperability of
the Web.</p>

<p>This is one document in a <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Introduction">set
of six</a> (<a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/">Primer</a>,
<a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/">Concepts</a>,
<a
href="http://www.w3.org/TR/2004/REC-rdf-syntax-grammar-20040210/">Syntax</a>,
<a
href="http://www.w3.org/TR/2004/REC-rdf-mt-20040210/">Semantics</a>,
<a
href="http://www.w3.org/TR/2004/REC-rdf-schema-20040210/">Vocabulary</a>,
and <a
href="http://www.w3.org/TR/2004/REC-rdf-testcases-20040210/">Test
Cases</a>) intended to jointly replace the original Resource
Description Framework specifications, <a
href="http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/">RDF Model and Syntax (1999
Recommendation)</a> and <a
href="http://www.w3.org/TR/2000/CR-rdf-schema-20000327/">RDF Schema
(2000 Candidate Recommendation)</a>.  It has been developed by the <a
href="http://www.w3.org/2001/sw/RDFCore/">RDF Core Working Group</a>
as part of the <a href="http://www.w3.org/2001/sw/">W3C Semantic Web
Activity</a> (<a href="http://www.w3.org/2001/sw/Activity">Activity
Statement</a>, <a
href="http://www.w3.org/2002/11/swv2/charters/RDFCoreWGCharter">Group
Charter</a>) for publication on 10 February 2004.
</p>

<p>Changes to this document since the <a
href="http://www.w3.org/TR/2003/PR-rdf-schema-20031215/"
shape="rect">Proposed Recommendation Working Draft</a> are detailed in
the <a href="#changes" shape="rect">change log</a>.  </p>

<p> The public is invited to send comments to <a
href="mailto:www-rdf-comments@w3.org">www-rdf-comments@w3.org</a> (<a
href="http://lists.w3.org/Archives/Public/www-rdf-comments/">archive</a>)
and to participate in general discussion of related technology on <a
href="mailto:www-rdf-interest@w3.org"
shape="rect">www-rdf-interest@w3.org</a> (<a
href="http://lists.w3.org/Archives/Public/www-rdf-interest/"
shape="rect">archive</a>).  </p>

<p>A list of <a href="http://www.w3.org/2001/sw/RDFCore/impls">
implementations</a> is available.</p>

<p>The W3C maintains a list of <a href="http://www.w3.org/2001/sw/RDFCore/ipr-statements" 
rel="disclosure">any patent disclosures related to this work</a>.</p>

<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 W3C 
publications and the latest revision of this technical report can be found in 
the <a href="http://www.w3.org/TR/">W3C technical reports index</a> at 
http://www.w3.org/TR/.</em></p> 

<!-- End Status-Of-This-Document Text -->

</div>


<h2><a id="ch_contents" name="ch_contents"></a> Contents</h2>

<blockquote>
  1. <a href="#ch_introduction">Introduction</a><br />
  2. <a href="#ch_classes">Classes</a><br />
  &nbsp; &nbsp; 2.1 <a href="#ch_resource">rdfs:Resource</a><br />
  &nbsp; &nbsp; 2.2 <a href="#ch_class">rdfs:Class</a><br />
  &nbsp; &nbsp; 2.3 <a href="#ch_literal">rdfs:Literal</a><br />
  &nbsp; &nbsp; 2.4 <a href="#ch_datatype">rdfs:Datatype</a><br />
  &nbsp; &nbsp; 2.5 <a href="#ch_xmlliteral">rdf:XMLLiteral</a><br />
  &nbsp; &nbsp; 2.6 <a href="#ch_property">rdf:Property</a><br />
  3. <a href="#ch_properties">Properties</a><br />
  &nbsp; &nbsp; 3.1 <a href="#ch_range">rdfs:range</a><br />
  &nbsp; &nbsp; 3.2 <a href="#ch_domain">rdfs:domain</a><br />
  &nbsp; &nbsp; 3.3 <a href="#ch_type">rdf:type</a><br />
  &nbsp; &nbsp; 3.4 <a href="#ch_subclassof">rdfs:subClassOf</a><br />
  &nbsp; &nbsp; 3.5 <a href="#ch_subpropertyof">rdfs:subPropertyOf</a><br />
  &nbsp; &nbsp; 3.6 <a href="#ch_label">rdfs:label</a><br />
  &nbsp; &nbsp; 3.7 <a href="#ch_comment">rdfs:comment</a><br />
  4. <a href="#ch_domainrange">Using the Domain and Range vocabulary
  (Informative)</a><br />
  5. <a href="#ch_othervocab">Other vocabulary</a><br />
  &nbsp; &nbsp; 5.1 <a href="#ch_containervocab">Container Classes and
  Properties</a> <br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.1 <a
  href="#ch_container">rdfs:Container</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.2 <a href="#ch_bag">rdf:Bag</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.3 <a href="#ch_seq">rdf:Seq</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.4 <a href="#ch_alt">rdf:Alt</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.5 <a
  href="#ch_containermembershipproperty">rdfs:ContainerMembershipProperty</a><br
  />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.1.6 <a href="#ch_member">rdfs:member</a><br />
  &nbsp; &nbsp; 5.2 <a href="#ch_collectionvocab">RDF Collections</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.2.1 <a href="#ch_list">rdf:List</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.2.2 <a href="#ch_first">rdf:first</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.2.3 <a href="#ch_rest">rdf:rest</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.2.4 <a href="#ch_nil">rdf:nil</a><br />
  &nbsp; &nbsp; 5.3 <a href="#ch_reificationvocab">Reification
  Vocabulary</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.3.1 <a
  href="#ch_statement">rdf:Statement</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.3.2 <a href="#ch_subject">rdf:subject</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.3.3 <a
  href="#ch_predicate">rdf:predicate</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.3.4 <a href="#ch_object">rdf:object</a><br />
  &nbsp; &nbsp; 5.4 <a href="#ch_utilvocab">Utility Properties</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.4.1 <a href="#ch_seealso">rdfs:seeAlso</a><br
  />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.4.2 <a
  href="#ch_isdefinedby">rdfs:isDefinedBy</a><br />
  &nbsp; &nbsp;&nbsp; &nbsp; 5.4.3 <a href="#ch_value">rdf:value</a><br />
  6. <a href="#ch_summary">RDF Schema summary (Informative)</a> <br />&nbsp; &nbsp;  6.1 <a href="#ch_sumclasses">Classes</a><br />
  &nbsp; &nbsp; 6.2 <a href="#ch_sumproperties">Properties</a><br />
  7. <a href="#ch_references">References</a> <br />&nbsp; &nbsp;  7.1 <a href="#ch_normreferences">Normative References</a><br
  /> &nbsp; &nbsp; 7.2 <a href="#ch_inforeferences">Informational
  References</a><br />
  8. <a href="#ch_acknowledgments">Acknowledgments</a><br />
  Appendix A <a href="#ch_appendix_rdfs">RDF Schema as RDF/XML</a><br />
</blockquote>
<hr />

<h2><a id="ch_introduction" name="ch_introduction"></a>1. Introduction</h2>

<p>The Resource Description Framework (RDF) is a general-purpose language for
representing information in the Web.</p>

<p>This specification is one of several [<a
href="#ref-rdf-primer">RDF-PRIMER</a>] [<a
href="#ref-rdf-syntax">RDF-SYNTAX</a>] [<a
href="#ref-rdf-concepts">RDF-CONCEPTS</a>] [<a
href="#ref-rdf-semantics">RDF-SEMANTICS</a>] [<a
href="#ref-rdf-tests">RDF-TESTS</a>] related to RDF. The reader is referred
to the <a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#rdfschema">RDF
schema chapter</a> in the RDF Primer [<a
href="#ref-rdf-primer">RDF-PRIMER</a>] for an informal introduction and
examples of the use of the concepts specified in this document.</p>

<p>This specification introduces RDF's vocabulary description language, RDF
Schema. It is complemented by several companion documents which describe
RDF's XML encoding [<a href="#ref-rdf-syntax">RDF-SYNTAX</a>], mathematical foundations [<a href="#ref-rdf-semantics">RDF-SEMANTICS</a>] and Resource
Description Framework (RDF): Concepts and Abstract Syntax [<a
href="#ref-rdf-concepts">RDF-CONCEPTS</a>]. The RDF Primer [<a
href="#ref-rdf-primer">RDF-PRIMER</a>] provides an informal introduction and
examples of the use of the concepts specified in this document.</p>

<p>This document is intended to provide a clear specification of the RDF
vocabulary description language to those who find the formal semantics
specification, RDF Semantics [<a href="#ref-rdf-semantics">RDF-SEMANTICS</a>]
daunting. Thus, this document duplicates material also specified in the RDF
Semantics specification . Where there is disagreement between this document
and the RDF Semantics specification, the RDF Semantics specification should
be taken to be correct.</p>

<p>RDF properties may be thought of as attributes of resources and in this sense correspond to traditional attribute-value pairs. RDF properties also represent relationships between resources.</p>

<p>RDF however, provides no mechanisms for describing these properties, nor
does it provide any mechanisms for describing the relationships between these
properties and other resources. That is the role of the RDF vocabulary
description language, RDF Schema. RDF Schema defines classes and properties
that may be used to describe classes, properties and other resources.</p>

<p>This document does not specify a vocabulary of descriptive properties such
as "author". Instead it specifies mechanisms that may be used to name and
describe properties and the classes of resource they describe.</p>

<p>
RDF's vocabulary description language, RDF Schema, is a 
semantic extension (as 
<a href="http://www.w3.org/TR/rdf-mt/#intro">defined</a> in [<a href="#ref-rdf-semantics">RDF-SEMANTICS</a>]) of RDF. It provides  
mechanisms for describing groups of related resources and the 
relationships between these resources.  RDF Schema vocabulary 
descriptions are written in RDF using the terms described in this document.
These resources are used to determine characteristics of other resources, 
such as the <a href="#ch_domain">domains</a> and 
<a href="#ch_range">ranges</a> of properties.
</p>

<p>The RDF vocabulary description language class and property system is similar to the type systems of object-oriented programming languages such as Java. RDF differs from many such systems in that instead of defining a class in terms of the properties its instances may have, the RDF vocabulary description language describes properties in terms of the classes of resource to which they apply. This is the role of the <a href="#ch_domain">domain</a> and <a href="#ch_range">range</a> mechanisms described in this specification. For example, we could define the <code>eg:author</code>
property to have a domain of <code>eg:Document</code> and a range of
<code>eg:Person</code>, whereas a classical object oriented system might
typically define a class <code>eg:Book</code> with an attribute called
<code>eg:author</code> of type <code>eg:Person</code>. Using the RDF approach, it is easy for others to subsequently define additional properties with a domain of eg:<code>Document</code> or a range of <code>eg:Person</code>.
This can be done without the need to re-define the original description of
these classes. One benefit of the RDF property-centric approach is that it
allows anyone to extend the description of existing resources, one of the
architectural principles of the Web [<a
href="#rdfnotcite">BERNERS-LEE98</a>].</p>

<p>This specification does not attempt to enumerate all the possible forms of
vocabulary description that are useful for representing the meaning of RDF
classes and properties. Instead, the RDF vocabulary description strategy is
to acknowledge that there are many techniques through which the meaning of
classes and properties can be described. Richer vocabulary or 'ontology'
languages such as DAML+OIL, W3C's [<a href="#ref-owl">OWL</a>] language, 
inference rule
languages and other formalisms (for example temporal logics) will each
contribute to our ability to capture meaningful generalizations about data in
the Web. RDF vocabulary designers can create and deploy Semantic Web
applications using the RDF vocabulary description language 1.0 facilities,
while exploring richer vocabulary description languages that share this
general approach.</p>

<p>The language defined in this specification consists of a collection 
of RDF resources that can be used to describe properties of other RDF 
resources (including properties) in application-specific RDF 
vocabularies. The core vocabulary is defined in a namespace informally 
called 'rdfs' here. That namespace is identified by the URI-Reference 
http://www.w3.org/2000/01/rdf-schema# and is associated with the prefix 
'rdfs'. This specification also uses the prefix 'rdf' to refer to the <a 
href="http://www.w3.org/TR/2004/REC-rdf-syntax-grammar-20040210/#section-Namespace">RDF 
namespace</a> http://www.w3.org/1999/02/22-rdf-syntax-ns#.</p>

<p>For convenience and readability, this specification uses an abbreviated
form to represent URI-References. A name of the form prefix:suffix should be
interpreted as a URI-Reference consisting of the URI-Reference associated
with the prefix concatenated with the suffix.</p>

<h2><a name="ch_classes" id="ch_classes">2. Classes</a></h2>

<p>Resources may be divided into groups called classes. The members of a
class are known as <em>instances</em> of the class. Classes are themselves
resources. They are often identified by <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Graph-URIref">RDF
URI References</a> and may be described using RDF properties. The <code><a
href="#ch_type">rdf:type</a></code> property may be used to state that a
resource is an instance of a class.</p>

<p>RDF distinguishes between a class and the set of its instances. Associated
with each class is a set, called the class extension of the class, which is
the set of the instances of the class. Two classes may have the same set of
instances but be different classes. For example, the tax office may define
the class of people living at the same address as the editor of this
document. The Post Office may define the class of people whose address has
the same zip code as the address of the author. It is possible for these
classes to have exactly the same instances, yet to have different properties.
Only one of the classes has the property that it was defined by the tax
office, and only the other has the property that it was defined by the Post
Office.</p>

<p>A class may be a member of its own class extension and may be an instance of itself. </p>

<p>The group of resources that are RDF Schema 
classes is itself a class called <a
href="#ch_class"><code>rdfs:Class</code></a>.</p>

<p><a name="def-subclass" id="def-subclass"></a>
If a class C is a <em>subclass</em> of a class C', then all instances of C will
also be instances of C'. 
The <a href="#ch_subclassof"><code>rdfs:subClassOf</code></a> property 
may be used to state that one class is a subclass of another. The term 
super-class is used as the inverse of subclass. If a class C' is a 
super-class of a class C, then all instances of C are also instances of C'.
</p>


		<p>The RDF Concepts and Abstract Syntax [<a
href="#ref-rdf-concepts">RDF-CONCEPTS</a>] specification defines the RDF
concept of an <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Datatypes">RDF
datatype</a>. All datatypes are classes. The instances of a class that is a
datatype are the members of the value space of the datatype.</p>
		<h4><a id="ch_resource" name="ch_resource" />2.1 rdfs:Resource</h4>
		<p>All things described by RDF are called <em>resources</em>, and are
instances of the class <code>rdfs:Resource</code>. This is the class of
everything. All other classes are <a href="#def-subclass">subclasses</a> of
this class. <code>rdfs:Resource</code> is an instance of <a
href="#ch_class"><code>rdfs:Class</code></a>.</p>
		<h4><a id="ch_class" name="ch_class"></a>2.2 rdfs:Class</h4>

<p>This is the class of resources that are RDF classes.
<code>rdfs:Class</code> is an instance of <code>rdfs:Class.</code></p>

<h4><a id="ch_literal" name="ch_literal"></a>2.3 rdfs:Literal</h4>

<p>The class <code>rdfs:Literal</code> is the class of <a href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Literals">literal</a> 
values such as strings and integers. Property values such as textual 
strings are examples of RDF literals. Literals may be <a href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-plain-literal">plain</a> 
or <a href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-typed-literal">typed</a>. A typed literal is an instance of a datatype class. This specification does not define the class of plain literals.</p>

<p><code>rdfs:Literal</code> is an instance of <a
href="#ch_class"><code>rdfs:Class</code></a>. rdfs:Literal is a <a
href="#def-subclass">subclass</a> of <a
href="#ch_resource">rdfs:Resource</a>.</p>

<h4><a id="ch_datatype" name="ch_datatype"></a>2.4 rdfs:Datatype</h4>

<p><code>rdfs:Datatype</code> is the class of datatypes. All instances of
<code>rdfs:Datatype</code> correspond to the <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Datatypes">RDF
model of a datatype</a> described in the RDF Concepts specification [<a
href="#ref-rdf-concepts">RDF-CONCEPTS</a>]. <code>rdfs:Datatype</code> is
both an instance of and a <a href="#def-subclass">subclass</a> of <a
href="#ch_class"><code>rdfs:Class</code></a>. Each instance of <code>rdfs:Datatype</code> is a <a href="#def-subclass">subclass</a> of rdfs:Literal.</p>

<h4><a id="ch_xmlliteral" name="ch_xmlliteral"></a>2.5 rdf:XMLLiteral</h4>

<p>The class <code>rdf:XMLLiteral</code> is the class of <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#dfn-rdf-XMLLiteral">XML
literal values</a>. <code>rdf:XMLLiteral</code> is an instance of
<code>rdfs:Datatype</code> and a <a href="#def-subclass">subclass</a> of <a
href="#ch_literal"><code>rdfs:Literal</code></a>.</p>

<h4><a id="ch_property" name="ch_property"></a>2.6 rdf:Property</h4>

<p><code>rdf:Property</code> is the class of RDF properties.
<code>rdf:Property</code> is an instance of <a
href="#ch_class"><code>rdfs:Class</code></a>.</p>

<h2><a name="ch_properties" id="ch_properties">3. Properties</a></h2>

<p>The RDF Concepts and Abstract Syntax specification [<a
href="#ref-rdf-concepts">RDF-CONCEPTS</a>] describes the concept of an RDF
property as a relation between subject resources and object resources.</p>

<p><a name="def-subproperty" id="def-subproperty"></a>
This specification defines the concept of subproperty. 
The <a href="#ch_subclassof"><code>rdfs:subPropertyOf</code></a> property 
may be used to state that one property is a subproperty of another.
If a property P is a subproperty of property P', then all pairs of resources which are 
related by P are also related by P'. The term super-property is often
used as the inverse of subproperty. If a property P' is a super-property
of a property P, then all pairs of resources which are related by P 
are also related by P'. This specification does not define a top
property that is the super-property of all properties.
</p>

<p>
<strong>Note</strong>: The basic facilities provided by 
<a href="#ch_domain"><code>rdfs:domain</code></a> and 
<a href="#ch_range"><code>rdfs:range</code></a> do not provide any direct 
way to indicate property restrictions that are local to a class. Although 
it is possible to combine use <a  
href="#ch_domain"><code>rdfs:domain</code></a> and <a href="#ch_range"><code>rdfs:range</code></a> 
with sub-property hierarchies, direct support for such declarations are 
provided by richer <a href="http://www.w3.org/2001/sw/WebOnt/">Web 
Ontology</a> languages such as [<a href="#ref-owl">OWL</a>].
</p>

<h4><a id="ch_range" name="ch_range"></a>3.1 rdfs:range</h4>

<p><code>rdfs:range</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state that
the values of a property are instances of one or more classes.</p>

<p>The triple</p>

<blockquote>
  <p>P rdfs:range C</p>
</blockquote>
		<p>states that P is an instance of the class <a
href="#ch_property"><code>rdf:Property</code></a>, that C is an instance of the class <a href="#ch_class"><code>rdfs:Class</code></a> and that the resources denoted by  the objects of triples whose predicate is P are instances of the class C.</p>
		<p>Where P has more than one rdfs:range property, then the resources denoted by the objects of triples with predicate P are instances of all the classes stated by the <code>rdfs:range</code> properties.</p>
		<p>The <code>rdfs:range</code> property can be applied to itself. The
rdfs:range of <code>rdfs:range</code> is the class <a
href="#ch_class"><code>rdfs:Class</code></a>. This states that any resource
that is the value of an <code>rdfs:range</code> property is an instance of <a
href="#ch_class"><code>rdfs:Class</code></a>.</p>
		<p>The <code>rdfs:range</code> property is applied to properties. This
can be represented in RDF using the <a
href="#ch_domain"><code>rdfs:domain</code></a> property. The <a
href="#ch_domain"><code>rdfs:domain</code></a> of <code>rdfs:range</code> is
the class <a href="#ch_property"><code>rdf:Property</code></a>. This states
that any resource with an <code>rdfs:range</code> property is an instance of
<code><a href="#ch_property">rdf:Property</a></code>.</p>
		<h4><a id="ch_domain" name="ch_domain" />3.2 rdfs:domain</h4>
		<p><code>rdfs:domain</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state that
any resource that has a given property is an instance of one or more
classes.</p>
		<p>A triple of the form:</p>

<blockquote>
  <p>P rdfs:domain C</p>
</blockquote>
		<p>states that P is an instance of the class <code><a href="#ch_property">rdf:Property</a></code>, that C is a instance of the class <code><a href="#ch_class">rdfs:Class</a></code> and that the resources denoted by the subjects of triples whose predicate is P are instances of the class C.</p>
		<p>Where a property P has more than one rdfs:domain property, then the resources denoted by subjects of triples with predicate P are instances of all the classes stated by the <code>rdfs:domain</code> properties.</p>
		<p>The <code>rdfs:domain</code> property may be applied to itself. The
rdfs:domain of <code>rdfs:domain</code> is the class <a
href="#ch_property"><code>rdf:Property</code></a>. This states that any
resource with an <code>rdfs:domain</code> property is an instance of <code><a
href="#ch_property">rdf:Property</a></code>.</p>
		<p>The <a href="#ch_range"><code>rdfs:range</code></a> of
<code>rdfs:domain</code> is the class <code><a href="#ch_class">rdfs:Class</a></code>. This states that any resource that is the value of an <code>rdfs:domain</code> property is an
instance of <code><a href="#ch_class">rdfs:Class</a></code>.</p>
		<h4><a id="ch_type" name="ch_type" />3.3 rdf:type</h4>
		<p><code>rdf:type</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state that
a resource is an instance of a class.</p>
		<p>A triple of the form:</p>

<blockquote>
  <p>R rdf:type C</p>
</blockquote>

<p>states that C is an instance of <a
href="#ch_class"><code>rdfs:Class</code></a> and R is an instance of C.</p>

<p>The <code><a href="#ch_domain">rdfs:domain</a></code> of
<code>rdf:type</code> is <a href="#ch_resource">rdfs:Resource</a>. The <a
href="#ch_range"><code>rdfs:range</code></a> of rdf:type is <a
href="#ch_class"><code>rdfs:Class</code></a>.</p>

<h4><a id="ch_subclassof" name="ch_subclassof"></a>3.4 rdfs:subClassOf</h4>
		<p>The property <code>rdfs:subClassOf</code> is an instance of <code><a href="#ch_property">rdf:Property</a></code> that is used to state that all the instances of one class are instances of another.</p>
		<p>A triple of the form:</p>
		<blockquote>
  <p>C1 rdfs:subClassOf C2</p>
</blockquote>

<p>states that C1 is an instance of <code><a
href="#ch_class">rdfs:Class</a></code>, C2 is an instance of <code><a
href="#ch_class">rdfs:Class</a></code> and C1 is a <a
href="#def-subclass">subclass</a> of C2. The <code>rdfs:subClassOf</code>
property is transitive.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdfs:subClassOf</code> is <code><a href="#ch_class">rdfs:Class</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of <code>rdfs:subClassOf</code>
is <a href="#ch_class"><code>rdfs:Class</code></a>.</p>

<h4><a id="ch_subpropertyof" name="ch_subpropertyof"></a>3.5
rdfs:subPropertyOf</h4>
		<p>The property <code>rdfs:subPropertyOf</code> is an instance of <code><a href="#ch_property">rdf:Property</a></code> that is used to state that all resources related by one property are also related by another.</p>
		<p>A triple of the form:</p>
		<blockquote>
  <p>P1 rdfs:subPropertyOf P2</p>
</blockquote>

<p>states that P1 is an instance of <code><a
href="#ch_property">rdf:Property</a></code>, P2 is an instance of <code><a
href="#ch_property">rdf:Property</a></code> and P1 is a <a
href="#def-subproperty">subproperty</a> of P2. The
<code>rdfs:subPropertyOf</code> property is transitive.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdfs:subPropertyOf</code> is <code><a
href="#ch_property">rdf:Property</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of rdfs:subPropertyOf is <a
href="#ch_property"><code>rdf:Property</code></a>.</p>

<h4><a id="ch_label" name="ch_label"></a>3.6 rdfs:label</h4>

<p><code>rdfs:label</code> is an instance of <a href="#ch_property"><code>rdf:Property</code></a> that may be used to provide a human-readable version of a resource's name.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>R rdfs:label L</p>
</blockquote>

<p>states that L is a human readable label for R.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdfs:label</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of rdfs:label is <a
href="#ch_literal"><code>rdfs:Literal</code></a>.</p>

<p>Multilingual labels are supported using the <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Graph-Literal">language
tagging</a> facility of RDF literals.</p>

<h4><a id="ch_comment" name="ch_comment"></a>3.7 rdfs:comment</h4>

<p><code>rdfs:comment</code> is an instance of <code><a href="#ch_property">rdf:Property</a></code> that may be used to provide a human-readable description of a resource.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>R rdfs:comment L</p>
</blockquote>

<p>states that L is a human readable description of R.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdfs:comment</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of rdfs:comment is <a
href="#ch_literal"><code>rdfs:Literal</code></a>.</p>

<p>A textual comment helps clarify the meaning of RDF classes and properties.
Such in-line documentation complements the use of both formal techniques
(Ontology and rule languages) and informal (prose documentation, examples,
test cases). A variety of documentation forms can be combined to indicate the
intended meaning of the classes and properties described in an RDF
vocabulary. Since RDF vocabularies are expressed as RDF graphs, vocabularies
defined in other namespaces may be used to provide richer documentation.</p>

<p>Multilingual documentation is supported through use of the <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-Graph-Literal">language
tagging</a> facility of RDF literals.</p>

<h2><a id="ch_domainrange" name="ch_domainrange"></a>4. Using the Domain and
Range Vocabulary (Informative)</h2>

<p>This specification introduces an RDF vocabulary for describing the
meaningful use of properties and classes in RDF data. For example, an RDF
vocabulary might describe limitations on the types of values that are
appropriate for some property, or on the classes to which it makes sense to
ascribe such properties.</p>

<p>The RDF Vocabulary Description language provides a mechanism for describing this information, but does not say whether or how an application should use it. For example, while an RDF vocabulary can assert that an <code>author</code> property is used to
indicate resources that are instances of the class <code>Person</code>, it
does not say whether or how an application should act in processing that
range information. Different applications will use this information in
different ways. For example, data checking tools might use this to help
discover errors in some data set, an interactive editor might suggest
appropriate values, and a reasoning application might use it to infer
additional information from instance data.</p>

<p>RDF vocabularies can describe relationships between vocabulary items from
multiple independently developed vocabularies. Since URI-References are used
to identify classes and properties in the Web, it is possible to create new
properties that have a <code>domain</code> or <code>range</code> whose value
is a class defined in another namespace.</p>

<h2><a id="ch_othervocab" name="ch_othervocab"></a>5. Other vocabulary</h2>

<p>Additional classes and properties, including constructs for representing
containers and RDF statements, and for deploying RDF vocabulary descriptions
in the World Wide Web are defined in this section.</p>

<h3><a id="ch_containervocab" name="ch_containervocab">5.1</a> Container
Classes and Properties</h3>

<p>RDF containers are resources that are used to represent collections. An <a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#containers">introduction</a>
to RDF containers with examples may be found in the RDF Primer [<a
href="#ref-rdf-primer">RDF-PRIMER</a>]. The same resource may appear in a
container more than once. Unlike containment in the physical world, a
container may be contained in itself.</p>

<p>Three different kinds of container are defined. Whilst the formal
semantics [<a href="#ref-rdf-semantics">RDF-SEMANTICS</a>] of all three classes of container are identical, different classes may be used to indicate informally further information. An rdf:Bag is used to indicate that the container is intended to be unordered. An rdf:Seq is used to indicate that the order indicated by the numerical order of the <a
href="#ch_containermembershipproperty">container member ship properties</a>
of the container is intended to be significant. An rdf:Alt container is used
to indicate that typical processing of the container will be to select one of
the members.</p>

<p>Just as a hen house may have the property that it is made of wood, that
does not mean that all the hens it contains are made of wood, a property of a
container is not necessarily a property of all of its members.</p>

<p>RDF containers are defined by the following classes and properties.</p>

<h4><a id="ch_container" name="ch_container"></a>5.1.1 rdfs:Container</h4>

<p>The <code>rdfs:Container</code> class is a super-class of the RDF
Container classes, i.e. <code><a href="#ch_bag">rdf:Bag</a></code>, <code><a
href="#ch_seq">rdf:Seq</a></code>, <code><a
href="#ch_alt">rdf:Alt</a></code>.</p>

<h4><a id="ch_bag" name="ch_bag"></a>5.1.2 rdf:Bag</h4>

<p>The <code>rdf:Bag</code> class is the class of RDF 'Bag' containers. It is
a <a href="#def-subclass">subclass</a> of <code><a
href="#ch_container">rdfs:Container</a></code>. Whilst formally it is no
different from an <code><a href="#ch_seq">rdf:Seq</a></code> or an <code><a
href="#ch_alt">rdf:Alt</a></code>, the <code>rdf:Bag</code> class is used
conventionally to indicate to a human reader that the container is intended
to be unordered.</p>

<h4><a id="ch_seq" name="ch_seq"></a>5.1.3 rdf:Seq</h4>

<p>The <code>rdf:Seq</code> class is the class of RDF 'Sequence' containers.
It is a <a href="#def-subclass">subclass</a> of <code><a
href="#ch_container">rdfs:Container</a></code>. Whilst formally it is no
different from an <code><a href="#ch_bag">rdf:Bag</a></code> or an <code><a
href="#ch_alt">rdf:Alt</a></code>, the <code>rdf:Seq</code> class is used
conventionally to indicate to a human reader that the numerical ordering of
the <a href="#ch_containermembershipproperty">container membership
properties</a> of the container is intended to be significant.</p>

<h4><a id="ch_alt" name="ch_alt"></a>5.1.4 rdf:Alt</h4>

<p>The <code>rdf:Alt</code> class is the class of RDF 'Alternative'
containers. It is a <a href="#def-subclass">subclass</a> of <code><a
href="#ch_container">rdfs:Container</a></code>. Whilst formally it is no
different from an <code><a href="#ch_seq">rdf:Seq</a></code> or an <code><a
href="#ch_bag">rdf:Bag</a></code>, the <code>rdf:Alt</code> class is used
conventionally to indicate to a human reader that typical processing will be
to select one of the members of the container. The first member of the
container, i.e. the value of the <code><a
href="#ch_containermembershipproperty">rdf:_1</a></code> property, is the
default choice.</p>

<h4><a id="ch_containermembershipproperty"
name="ch_containermembershipproperty"></a>5.1.5
rdfs:ContainerMembershipProperty</h4>

<p>The <code>rdfs:ContainerMembershipProperty</code> class has as instances
the properties <code>rdf:_1, rdf:_2, rdf:_3 ...</code> that are used to state
that a resource is a member of a container.
<code>rdfs:ContainerMembershipProperty</code> is a <a
href="#def-subclass">subclass</a> of <a
href="#ch_property"><code>rdf:Property</code></a>. Each instance of
<code>rdfs:ContainerMembershipProperty</code> is an <a
href="#ch_subpropertyof"><code>rdfs:subPropertyOf</code></a> the <code><a
href="#ch_member">rdfs:member</a></code> property.</p>

<p>Given a container C, a triple of the form:</p>

<blockquote>
  <p>C rdf:_nnn O</p>
</blockquote>

<p>where nnn is the decimal representation of an integer greater than 0 with
no leading zeros, states that O is a member of the container C.</p>

<p>Container membership properties may be applied to resources other than containers.</p>

<h4><a id="ch_member" name="ch_member"></a>5.1.6 rdfs:member</h4>

<p><code>rdfs:member</code> is an instance of <code><a
href="#ch_property">rdf:Property</a></code> that is a super-property of all
the container membership properties i.e. each container membership property
has an <a href="#ch_subpropertyof"><code>rdfs:subPropertyOf</code></a>
relationship to the property <code>rdfs:member</code>.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdfs:member</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of <code>rdfs:member</code> is
<code><a href="#ch_resource">rdfs:Resource</a></code>.</p>

<h3><a id="ch_collectionvocab" name="ch_collectionvocab">5.2</a> RDF
Collections</h3>

<p>RDF containers are open in the sense that the core RDF specifications
define no mechanism to state that there are no more members. The RDF
Collection vocabulary of classes and properties can describe a closed
collection, i.e. one that can have no more members. The reader is referred to
the <a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#collections">collections</a>
section of the RDF primer for an informal introduction to collections with
examples.</p>

<p>A collection is represented as a list of items, a representation that 
will be familiar to those with experience of Lisp and similar 
programming languages. There is a <a 
href="http://www.w3.org/TR/2004/REC-rdf-syntax-grammar-20040210/#section-Syntax-parsetype-Collection">shorthand notation</a> in the RDF/XML syntax specification [<a href="#ref-rdf-syntax">RDF-SYNTAX</a>] for representing collections.</p>

<p><strong>Note</strong>:  RDFS does not require that there be only one 
first element of a list-like structure, or even that a list-like structure 
have a first element.
</p>


<h4><a id="ch_list" name="ch_list"></a>5.2.1 rdf:List</h4>

<p><code>rdf:List</code> is an instance of <a href="#ch_class"><code>rdfs:Class</code></a> 
that can be used to build descriptions of lists and other list-like structures.
</p>

<h4><a id="ch_first" name="ch_first"></a>5.2.2 rdf:first</h4>

<p><code>rdf:first</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that can be used to 
build descriptions of lists and other list-like structures.
</p>

<p>A triple of the form:</p>

<blockquote>
  <p>L rdf:first O</p>
</blockquote>

<p>states that there is a first-element relationship between L and O.</p>

<p>
The <a href="#ch_domain"><code>rdfs:domain</code></a> of 
<code>rdf:first</code> is <code><a href="#ch_list">rdf:List</a></code>. 
The <a href="#ch_range"><code>rdfs:range</code></a> of 
<code>rdf:first</code> is <code><a href="#ch_resource">rdfs:Resource</a></code>. 
</p>

<h4><a id="ch_rest" name="ch_rest"></a>5.2.3 rdf:rest</h4>

<p><code>rdf:rest</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that can be used to 
build descriptions of lists and other list-like structures.
</p>

<p>A triple of the form:</p>

<blockquote>
  <p>L rdf:rest O</p>
</blockquote>

<p>states that there is a rest-of-list relationship between L and O.</p>

<p>
The <a href="#ch_domain"><code>rdfs:domain</code></a> of 
<code>rdf:rest</code> is <code><a href="#ch_list">rdf:List</a></code>. 
The <a href="#ch_range"><code>rdfs:range</code></a> of 
<code>rdf:rest</code> is <code><a href="#ch_list">rdf:List</a></code>. 

</p>

<h4><a id="ch_nil" name="ch_nil"></a>5.2.4 rdf:nil</h4>

<p>The resource <code>rdf:nil</code> is an instance of <code><a
href="#ch_list">rdf:List</a></code> that can be used to represent an 
empty list or other list-like structure.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>L rdf:rest rdf:nil</p>
</blockquote>

<p>states that L is an instance of <code><a
href="#ch_list">rdf:List</a></code> that has one item; that item can be 
indicated using the <code><a href="#ch_first">rdf:first</a></code> property.</p>

<h3><a id="ch_reificationvocab" name="ch_reificationvocab">5.3</a>
Reification Vocabulary</h3>



<p>
The original RDF Model and Syntax Specification [<a 
href="#rdfmscite">RDFMS</a>] defined a 
vocabulary for describing RDF statements without stating them. [<a href="#rdfmscite">RDFMS</a>]
did not provide a formal semantics for this vocabulary, and the informal 
definition that was provided was somewhat inconsistent. 
The current RDF specification does not assign a normative 
formal semantics to this vocabulary.  However, an intended meaning of 
this vocabulary (which generally clarifies the intent of the 
[<a href="#rdfmscite">RDFMS</a>] definition) is described here.
An informal introduction to the reification vocabulary, with examples, 
may be found in the RDF Primer [<a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#reification">RDF-PRIMER</a>].
</p>

<h4><a id="ch_statement" name="ch_statement"></a>5.3.1 rdf:Statement</h4>


<p>
<code>rdf:Statement</code> is an instance of 
<code><a href="#ch_class">rdfs:Class.</a></code> 
It is intended to represent the class of RDF statements. An RDF statement is the 
statement made by a token of an RDF 
<a 
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-triples">triple</a>. 
The subject of an RDF statement is the instance of 
<code><a
href="#ch_resource">rdfs:Resource</a></code> 
identified by the subject of the triple. The predicate of an RDF 
statement is the instance of <code><a
href="#ch_property">rdf:Property</a></code>
identified by the predicate 
of the triple. The object of an RDF statement is the instance of 
<code><a
href="#ch_resource">rdfs:Resource</a></code> 
identified by the object of the triple.
<code>rdf:Statement</code> 
is in the domain of the properties 
<code><a href="#ch_predicate">rdf:predicate</a></code>, 
<code><a href="#ch_subject">rdf:subject</a></code>
and 
<code><a href="#ch_object">rdf:object</a></code>. 
Different individual <code>rdf:Statement</code> 
instances may have the same values for their 
<code><a href="#ch_predicate">rdf:predicate</a></code>, 
<code><a href="#ch_subject">rdf:subject</a></code>
and <code><a href="#ch_object">rdf:object</a></code> properties.
</p>

<h4><a id="ch_subject" name="ch_subject"></a>5.3.2 rdf:subject</h4>

<p><code>rdf:subject</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state the
subject of a statement.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>S rdf:subject R</p>
</blockquote>

<p>states that S is an instance of <code><a
href="#ch_statement">rdf:Statement</a></code> and that the subject of S is
R.</p>

<p class="schemacomment">The <a
href="#ch_domain"><code>rdfs:domain</code></a> of <code>rdf:subject</code> is
<code><a href="#ch_statement">rdf:Statement</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of <code>rdf:subject</code> is
<code><a href="#ch_resource">rdfs:Resource</a></code>.</p>

<h4><a id="ch_predicate" name="ch_predicate"></a>5.3.3 rdf:predicate</h4>

<p>rdf:predicate is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state the
predicate of a statement.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>S rdf:predicate P</p>
</blockquote>

<p>states that S is an instance of <code><a
href="#ch_statement">rdf:Statement</a></code>, that P is an instance of
<code><a href="#ch_property">rdf:Property</a></code> and that the <a
href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/#section-data-model">predicate</a>
of S is P.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdf:predicate</code> is <code><a
href="#ch_statement">rdf:Statement</a></code> and the <a
href="#ch_range"><code>rdfs:range</code></a> is <a
href="#ch_resource"><code>rdfs:Resource</code></a>.</p>

<h4><a id="ch_object" name="ch_object"></a>5.3.4 rdf:object</h4>

<p>rdf:object is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to state the
object of a statement.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>S rdf:object O</p>
</blockquote>

<p>states that S is an instance of <code><a
href="#ch_statement">rdf:Statement</a></code> and that the object of S is
O.</p>

<p>The <a href="#ch_domain"><code>rdfs:domain</code></a> of
<code>rdf:object</code> is <code><a
href="#ch_statement">rdf:Statement</a></code>. The <a
href="#ch_range"><code>rdfs:range</code></a> of <code>rdf:object</code> is
<code><a href="#ch_resource">rdfs:Resource</a></code>.</p>

<h3><a id="ch_utilvocab" name="ch_utilvocab"></a>5.4 Utility Properties</h3>

<p>The following utility classes and properties are defined in the RDF core
namespaces.</p>

<h4><a id="ch_seealso" name="ch_seealso"></a>5.4.1 rdfs:seeAlso</h4>

<p><code>rdfs:seeAlso</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to indicate a
resource that might provide additional information about the subject
resource.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>S rdfs:seeAlso O</p>
</blockquote>

<p>states that the resource O may provide additional information about S. It
may be possible to retrieve representations of O from the Web, but this is
not required. When such representations may be retrieved, no constraints are
placed on the format of those representations.</p>

<p>The <code><a href="#ch_domain">rdfs:domain</a></code> of
<code>rdfs:seeAlso</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <code><a
href="#ch_range">rdfs:range</a></code> of <code>rdfs:seeAlso</code> is
<code><a href="#ch_resource">rdfs:Resource</a></code>.</p>

<h4><a id="ch_isdefinedby" name="ch_isdefinedby"></a>5.4.2
rdfs:isDefinedBy</h4>

<p><code>rdfs:isDefinedBy</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that is used to indicate a
resource defining the subject resource. This property may be used to indicate
an RDF vocabulary in which a resource is described.</p>

<p>A triple of the form:</p>

<blockquote>
  <p>S rdfs:isDefinedBy O</p>
</blockquote>

<p>states that the resource O defines S. It may be possible to retrieve
representations of O from the Web, but this is not required. When such
representations may be retrieved, no constraints are placed on the format of
those representations. <code>rdfs:isDefinedBy</code> is a <a
href="#def-subproperty">subproperty</a> of <code><a
href="#ch_seealso">rdfs:seeAlso</a></code>.</p>

<p>The <code><a href="#ch_domain">rdfs:domain</a></code> of
<code>rdfs:isDefinedBy</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <code><a
href="#ch_range">rdfs:range</a></code> of <code>rdfs:isDefinedBy</code> is
<code><a href="#ch_resource">rdfs:Resource</a></code>.</p>

<h4><a id="ch_value" name="ch_value"></a>5.4.3 rdf:value</h4>

<p><code>rdf:value</code> is an instance of <a
href="#ch_property"><code>rdf:Property</code></a> that may be used in
describing structured values.</p>

<p>rdf:value has no meaning on its own. It is provided as a piece of
vocabulary that may be used in idioms such as illustrated in <a
href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#example16">example
16</a> of the RDF primer [<a href="#ref-rdf-primer">RDF-PRIMER</a>]. Despite
the lack of formal specification of the meaning of this property, there is
value in defining it to encourage the use of a common idiom in examples of
this kind.</p>

<p>The <code><a href="#ch_domain">rdfs:domain</a></code> of
<code>rdf:value</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>. The <code><a
href="#ch_range">rdfs:range</a></code> of <code>rdf:value</code> is <code><a
href="#ch_resource">rdfs:Resource</a></code>.</p>

<h2><a id="ch_summary" name="ch_summary"></a>6. RDF Schema summary (Informative)</h2>

<p>This table presents an overview of the vocabulary of RDF, drawing together
vocabulary originally defined in the RDF Model and Syntax specification with
classes and properties that originate with RDF Schema.</p>

<h3><a id="ch_sumclasses" name="ch_sumclasses"></a>6.1 RDF classes</h3>

<table border="1" summary="RDF classes">
  <tbody valign="top">
    <tr>
      <th>Class name</th>
      <th>comment</th>
    </tr>
    <tr>
      <td>rdfs:Resource</td>
      <td>The class resource, everything.</td>
    </tr>
    <tr>
      <td>rdfs:Literal</td>
      <td>The class of literal values, e.g. textual strings and integers.</td>
    </tr>
    <tr>
      <td>rdf:XMLLiteral</td>
      <td>The class of XML literals values.</td>
    </tr>
    <tr>
      <td>rdfs:Class</td>
      <td>The class of classes.</td>
    </tr>
    <tr>
      <td>rdf:Property</td>
      <td>The class of RDF properties.</td>
    </tr>
    <tr>
      <td>rdfs:Datatype</td>
      <td>The class of RDF datatypes.</td>
    </tr>
    <tr>
      <td>rdf:Statement</td>
      <td>The class of RDF statements.</td>
    </tr>
    <tr>
      <td>rdf:Bag</td>
      <td>The class of unordered containers.</td>
    </tr>
    <tr>
      <td>rdf:Seq</td>
      <td>The class of ordered containers.</td>
    </tr>
    <tr>
      <td>rdf:Alt</td>
      <td>The class of containers of alternatives.</td>
    </tr>
    <tr>
      <td>rdfs:Container</td>
      <td>The class of RDF containers.</td>
    </tr>
    <tr>
      <td>rdfs:ContainerMembershipProperty</td>
      <td>The class of container membership properties, rdf:_1, rdf:_2, ...,
        all of which are sub-properties of 'member'.</td>
    </tr>
    <tr>
      <td>rdf:List</td>
      <td>The class of RDF Lists.</td>
    </tr>
  </tbody>
</table>

<h3><a id="ch_sumproperties" name="ch_sumproperties"></a>6.2 RDF
properties</h3>

<table border="1" summary="RDF properties">
  <tbody valign="top">
    <tr>
      <th>Property name</th>
      <th>comment</th>
      <th>domain</th>
      <th>range</th>
    </tr>
    <tr>
      <td>rdf:type</td>
      <td>The subject is an instance of a class.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Class</td>
    </tr>
    <tr>
      <td>rdfs:subClassOf</td>
      <td>The subject is a subclass of a class.</td>
      <td>rdfs:Class</td>
      <td>rdfs:Class</td>
    </tr>
    <tr>
      <td>rdfs:subPropertyOf</td>
      <td>The subject is a subproperty of a property.</td>
      <td>rdf:Property</td>
      <td>rdf:Property</td>
    </tr>
    <tr>
      <td>rdfs:domain</td>
      <td>A domain of the subject property.</td>
      <td>rdf:Property</td>
      <td>rdfs:Class</td>
    </tr>
    <tr>
      <td>rdfs:range</td>
      <td>A range of the subject property.</td>
      <td>rdf:Property</td>
      <td>rdfs:Class</td>
    </tr>
    <tr>
      <td>rdfs:label</td>
      <td>A human-readable name for the subject.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Literal</td>
    </tr>
    <tr>
      <td>rdfs:comment</td>
      <td>A description of the subject resource.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Literal</td>
    </tr>
    <tr>
      <td>rdfs:member</td>
      <td>A member of the subject resource.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:first</td>
      <td>The first item in the subject RDF list.</td>
      <td>rdf:List</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:rest</td>
      <td>The rest of the subject RDF list after the first item.</td>
      <td>rdf:List</td>
      <td>rdf:List</td>
    </tr>
    <tr>
      <td>rdfs:seeAlso</td>
      <td>Further information about the subject resource.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdfs:isDefinedBy</td>
      <td>The definition of the subject resource.</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:value</td>
      <td>Idiomatic property used for structured values (see the RDF Primer for <a
        href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/#example16">an
        example</a> of its usage).</td>
      <td>rdfs:Resource</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:subject</td>
      <td>The subject of the subject RDF statement.</td>
      <td>rdf:Statement</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:predicate</td>
      <td>The predicate of the subject RDF statement.</td>
      <td>rdf:Statement</td>
      <td>rdfs:Resource</td>
    </tr>
    <tr>
      <td>rdf:object</td>
      <td>The object of the subject RDF statement.</td>
      <td>rdf:Statement</td>
      <td>rdfs:Resource</td>
    </tr>
  </tbody>
</table>

<p>In addition to these classes and properties, RDF also uses properties
called <code>rdf:_1</code>, <code>rdf:_2</code>, <code>rdf:_3</code>... etc.,
each of which is both a sub-property of <code>rdfs:member</code> and an
instance of the class <code>rdfs:ContainerMembershipProperty</code>. There is
also an instance of <code>rdf:List</code> called <code>rdf:nil</code> that is
an empty <code>rdf:List</code>.</p>

<h3><a id="ch_cores" name="ch_cores"></a></h3>
<hr />

<h2><a id="ch_references" name="ch_references">7.</a>References</h2>

<h3><a id="ch_normreferences" name="ch_normreferences"></a>7.1 Normative
References</h3>
<dl>



          <dt><a id="ref-rdf-concepts"
          name="ref-rdf-concepts"></a>[RDF-CONCEPTS]</dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/">Resource Description Framework (RDF): Concepts and Abstract Syntax</a></cite>, Graham Klyne and Jeremy J. Carroll, Editors, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-rdf-concepts-20040210/ . <a href="http://www.w3.org/TR/rdf-concepts/">Latest version</a> available at http://www.w3.org/TR/rdf-concepts/ .</dd>


          <dt><a id="ref-rdf-semantics"
          name="ref-rdf-semantics"></a>[RDF-SEMANTICS]</dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-rdf-mt-20040210/">RDF Semantics</a></cite>, Patrick Hayes, Editor, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-rdf-mt-20040210/ . <a href="http://www.w3.org/TR/rdf-mt/">Latest version</a> available at http://www.w3.org/TR/rdf-mt/ .</dd>

          <dt><a id="ref-rdf-syntax"
          name="ref-rdf-syntax"></a>[RDF-SYNTAX]</dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-rdf-syntax-grammar-20040210/">RDF/XML Syntax Specification (Revised)</a></cite>, Dave Beckett, Editor, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-rdf-syntax-grammar-20040210/ . <a href="http://www.w3.org/TR/rdf-syntax-grammar/">Latest version</a> available at http://www.w3.org/TR/rdf-syntax-grammar/ .</dd>

          <dt><a id="ref-rdf-tests"
          name="ref-rdf-tests"></a>[RDF-TESTS]</dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-rdf-testcases-20040210/">RDF Test Cases</a></cite>, Jan Grant and Dave Beckett, Editors, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-rdf-testcases-20040210/ . <a href="http://www.w3.org/TR/rdf-testcases/">Latest version</a> available at http://www.w3.org/TR/rdf-testcases/ .</dd>



  <dt><a id="rdfmscite" name="rdfmscite"></a> [RDFMS]</dt>
    <dd><a
      href="http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/"><cite>Resource
      Description Framework (RDF) Model and Syntax</cite></a>, W3C
      Recommendation, 22 February 1999<br />
      <small><tt><a
      href="http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/">http://www.w3.org/TR/1999/REC-rdf-syntax-19990222/</a></tt></small><br
      />
    </dd>
  <dt><a id="xmlnscite" name="xmlnscite"></a>[XMLNS]</dt>
    <dd><a
      href="http://www.w3.org/TR/1999/REC-xml-names-19990114/"><cite>Namespaces
      in XML</cite></a>; W3C Recommendation, 14 January 1999<br />
      <small><tt><a
      href="http://www.w3.org/TR/1999/REC-xml-names-19990114/">http://www.w3.org/TR/1999/REC-xml-names-19990114/</a></tt></small><br
      />
    </dd>
</dl>

<h3><a id="ch_inforeferences" name="ch_inforeferences"></a>7.2 Informational
References</h3>
<dl>

  <dt><a id="ref-rdf-primer" name="ref-rdf-primer">[RDF-PRIMER]</a>
  </dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-rdf-primer-20040210/">RDF Primer</a></cite>, Frank Manola and Eric Miller, Editors, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-rdf-primer-20040210/ . <a href="http://www.w3.org/TR/rdf-primer/">Latest version</a> available at http://www.w3.org/TR/rdf-primer/ .</dd>


  <dt><a id="rdfnotcite" name="rdfnotcite">[BERNERS-LEE98]</a></dt>
    <dd><a href="http://www.w3.org/DesignIssues/RDFnot.html"><cite>What the
      Semantic Web can represent</cite></a>, Tim Berners-Lee, 1998<br />
      <small><tt><a 
      href="http://www.w3.org/DesignIssues/RDFnot.html">http://www.w3.org/DesignIssues/RDFnot.html</a></tt></small><br
      />
    </dd>
  <dt><a id="xlcite" name="xlcite"></a>[EXTWEB]</dt>
    <dd><a
      href="http://www.w3.org/TR/1998/NOTE-webarch-extlang-19980210"><cite>Web
      Architecture: Extensible Languages</cite></a>, Tim Berners-Lee and Dan
      Connolly, 1998<br />
      <small><tt><a
      href="http://www.w3.org/TR/1998/NOTE-webarch-extlang-19980210">http://www.w3.org/TR/1998/NOTE-webarch-extlang-19980210</a></tt></small><br
      />
    </dd>
  <dt><a id="ref_dcmi" name="ref_dcmi"></a> [DCMI]</dt>
    <dd><a href="http://www.dublincore.org/"><cite>Dublin Core Metadata
      Initiative</cite></a><br />
      <small><tt><a
      href="http://www.dublincore.org/">http://www.dublincore.org/</a></tt></small><br
      />
    </dd>

  <dt><a id="ref-owl" name="ref-owl"></a>[OWL]</dt>
<dd><cite><a href="http://www.w3.org/TR/2004/REC-owl-ref-20040210/">OWL Web Ontology Language Reference</a></cite>, Mike Dean and Guus Schreiber, Editors, W3C Recommendation, 10 February 2004, http://www.w3.org/TR/2004/REC-owl-ref-20040210/ . <a href="http://www.w3.org/TR/owl-ref/">Latest version</a> available at http://www.w3.org/TR/owl-ref/ .</dd>


  <dt><a id="cccite" name="cccite"></a>[SCHEMA-ARCH]</dt>
    <dd><a
      href="http://www.w3.org/TR/1999/NOTE-schema-arch-19991007"><cite>The
      Cambridge Communiqué</cite></a>, W3C NOTE, 7 October 1999, Swick and
      Thompson<br />
      <small><tt><a
      href="http://www.w3.org/TR/1999/NOTE-schema-arch-19991007">http://www.w3.org/TR/1999/NOTE-schema-arch-19991007</a></tt></small><br
      />
    </dd>
  <dt><a id="dtdcite" name="dtdcite"></a>[XML]</dt>
    <dd><a href="http://www.w3.org/TR/1998/REC-xml-19980210"><cite>Extensible
      Markup Language (XML) 1.0</cite></a>, W3C Recommendation,
      10-February-1988, Section 3.2 Element Type Declarations<br />
      <small><tt><a
      href="http://www.w3.org/TR/1998/REC-xml-19980210.html#elemdecls">http://www.w3.org/TR/1998/REC-xml-19980210.html#elemdecls</a></tt></small><br
      />
    </dd>
</dl>

<h2><a id="ch_acknowledgements" name="ch_acknowledgements"></a> <a
id="ch_acknowledgments" name="ch_acknowledgments"></a>8. Acknowledgments</h2>

<p>The RDF Schema design was originally produced by the RDF Schema Working
Group (1997-2000). The current specification is largely an editorial
clarification of that design, and has benefited greatly from the hard work of
the <a href="http://www.w3.org/2001/sw/RDFCore/">RDF Core Working Group</a>
<a href="http://www.w3.org/2001/sw/RDFCore/#Membership">members</a>, and from
implementation feedback from many members of the <a
href="http://www.w3.org/RDF/Interest/">RDF Interest Group</a>.</p>

<p>David Singer of IBM was the chair of the original RDF Schema group
throughout most of the development of this specification; we thank David for
his efforts and thank IBM for supporting him and us in this endeavor.
Particular thanks are also due to Andrew Layman for his editorial work on
early versions of this specification.</p>

<p>The original RDF Schema Working Group membership included:</p>

<p>Nick Arnett (Verity), Dan Brickley (ILRT / University of Bristol), Walter
Chang (Adobe), Sailesh Chutani (Oracle), Ron Daniel (DATAFUSION), Charles
Frankston (Microsoft), Joe Lapp (webMethods Inc.), Patrick Gannon
(CommerceNet), RV Guha (Epinions, previously of Netscape Communications), Tom
Hill (Apple Computer), Renato Iannella (DSTC), Sandeep Jain (Oracle), Kevin
Jones, (InterMind), Emiko Kezuka (Digital Vision Laboratories), Ora Lassila
(Nokia Research Center), Andrew Layman (Microsoft), John McCarthy (Lawrence
Berkeley National Laboratory), Michael Mealling (Network Solutions), Norbert
Mikula (DataChannel), Eric Miller (OCLC), Frank Olken (Lawrence Berkeley
National Laboratory), Sri Raghavan (Digital/Compaq), Lisa Rein (webMethods
Inc.), Tsuyoshi Sakata (Digital Vision Laboratories), Leon Shklar (Pencom Web
Works), David Singer (IBM), Wei (William) Song (SISU), Neel Sundaresan (IBM),
Ralph Swick (W3C), Naohiko Uramoto (IBM), Charles Wicksteed (Reuters Ltd.),
Misha Wolf (Reuters Ltd.)</p>

<h2><a id="ch_appendix_figs" name="ch_appendix_figs"></a></h2>

<h2><a id="changes" name="changes"></a>Changes</h2>

<p>
The following is an outline of the main changes made to this specification, latest first, 
since the Last Call Working Draft of <a href="http://www.w3.org/TR/2003/WD-rdf-schema-20030123/">23 
January 2003</a>. See the <a href="http://www.w3.org/2001/sw/RDFCore/20030123-issues/#schema">Last Call issue tracking 
document</a> for details of the specific issues raised regarding this specification.
</p>

<ul>
<li>Amended <a href="#ch_appendix_rdfs">Appendix A</a> to note that the RDF/XML description of RDF and RDFS 
terms is not directly published at the RDFS namespace, but split between the 'rdf:' and 'rdfs:' namespace documents. 
Also removed the pre-REC warning that the WG might choose to change the namespace URI prior to Recommendation.</li>
<li>Amended rdfs:range specification for rdf:predicate for consistency with the Semantics document (previously rdf:Property; now, rdfs:Resource)</li>
<li>Removed reference to RDF mimetypes doc, as the IETF draft has expired and is 404 missing on their site.</li> 
<li>Reification vocabulary redescribed (<a href="http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Aug/0161.html">details</a>).</li>
<li>Reworded rdfs:comment for rdfs:member, changing "container" to "resource"</li>
<li>Reworded lead-in to Appendix A per <a 
href="http://lists.w3.org/Archives/Public/www-rdf-comments/2003JulSep/0170.html">0170.html</a>.
</li>
<li>OWL references now go to OWL specs rather than WebOnt homepage. Fixed minor typos per <a 
href="http://lists.w3.org/Archives/Public/www-rdf-comments/2003JanMar/0373.html">0373.html</a>)</li>
<li>Reworded rdf:nil to tone down the imperative style.</li>
<li>Added note to Properties section warning about over-use of sub-property,
and referencing OWL, an editorial suggestion from Bijan Parsia. (<a 
href="http://lists.w3.org/Archives/Public/www-rdf-comments/2003AprJun/0177.html">details</a>).
</li>
<li>Regarding <a 
href="http://www.w3.org/2001/sw/RDFCore/20030123-issues/#pfps-12">pfps-12</a>, <a 
href="http://lists.w3.org/Archives/Public/www-rdf-comments/2003AprJun/0277.html">discussion</a> 
led to rdf:first/rest/List/nil rewritten per Peter Patel-Schneider's suggestion.</li>
<li>Change to description of subProperty and subClass, to match <a 
href="http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#change">changes to RDF 
Semantics</a>. See
<a href="http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Jul/0161.html">discussion</a> 
for details.</li>
<li>Edits <a 
href="http://lists.w3.org/Archives/Public/www-rdf-comments/2003AprJun/0099.html">closing</a> 
'what is rdf schema' issue by clarifying that RDFS is a semantic extension of RDF, as defined 
in the RDF Semantics document. This closes rdfcore last call issue pfps-24.</li>
</ul>



<h2><a id="ch_appendix_rdfs" name="ch_appendix_rdfs"></a>Appendix A: RDF
Schema as RDF/XML</h2>

<p>
An RDFS description of the <a href="http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#InterpVocab">RDF vocabulary</a> 
and <a href="http://www.w3.org/TR/2004/REC-rdf-mt-20040210/#rdfs_interp">RDFS vocabulary</a> is given here in RDF/XML syntax. 
It includes statements describing RDF resources originally introduced by
the 1999 RDF Model and Syntax specification, as well as definitions for
resources introduced in the RDF Core Schema vocabulary.</p>

<p>
This material is also available as <a href="rdfs-namespace">a separate
RDF/XML document</a>. It does not necessarily match the content
published at the <a
href="http://www.w3.org/1999/02/22-rdf-syntax-ns#">RDF namespace
URI</a> or the <a href="http://www.w3.org/2000/01/rdf-schema#">RDFS
namespace URI</a>, which may evolve over time.
</p>

<table cellpadding="5" border="1" width="95%" summary="RDF Schema in RDF">
  <tbody>
    <tr>
      <td>
        <pre>
&lt;rdf:RDF
  xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
  xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
  xmlns:owl="http://www.w3.org/2002/07/owl#"&gt;

&lt;owl:Ontology rdf:about="http://www.w3.org/2000/01/rdf-schema#"/&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#Resource"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;Resource&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class resource, everything.&lt;/rdfs:comment&gt;
&lt;/rdfs:Class&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#type"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;type&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The subject is an instance of a class.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#Class"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;Class&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of classes.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#subClassOf"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;subClassOf&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The subject is a subclass of a class.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#subPropertyOf"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;subPropertyOf&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The subject is a subproperty of a property.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/&gt;
&lt;/rdf:Property&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;Property&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of RDF properties.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#comment"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;comment&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;A description of the subject resource.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Literal"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#label"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;label&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;A human-readable name for the subject.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Literal"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#domain"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;domain&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;A domain of the subject property.&lt;/rdfs:comment&gt;
 &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#range"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;range&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;A range of the subject property.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#seeAlso"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;seeAlso&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;Further information about the subject resource.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:domain   rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#isDefinedBy"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:subPropertyOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#seeAlso"/&gt;
  &lt;rdfs:label&gt;isDefinedBy&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The defininition of the subject resource.&lt;/rdfs:comment&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#Literal"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;Literal&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of literal values, eg. textual strings and integers.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;Statement&lt;/rdfs:label&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:comment&gt;The class of RDF statements.&lt;/rdfs:comment&gt;
&lt;/rdfs:Class&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#subject"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;subject&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The subject of the subject RDF statement.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;predicate&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The predicate of the subject RDF statement.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#object"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;object&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The object of the subject RDF statement.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Statement"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#Container"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;Container&lt;/rdfs:label&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:comment&gt;The class of RDF containers.&lt;/rdfs:comment&gt;
&lt;/rdfs:Class&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Bag"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;Bag&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of unordered containers.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Container"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Seq"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;Seq&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of ordered containers.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Container"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#Alt"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;Alt&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of containers of alternatives.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Container"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#ContainerMembershipProperty"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;ContainerMembershipProperty&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of container membership properties, rdf:_1, rdf:_2, ...,
                    all of which are sub-properties of 'member'.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#Property"/&gt;
&lt;/rdfs:Class&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/2000/01/rdf-schema#member"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;member&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;A member of the subject resource.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#value"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;value&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;Idiomatic property used for structured values.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;!-- the following are new additions, Nov 2002 --&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#List"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;List&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of RDF Lists.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;&lt;/rdfs:Class&gt;

&lt;rdf:List rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#nil"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;nil&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The empty list, with no items in it. If the rest of a list is nil then the list has no more items in it.&lt;/rdfs:comment&gt;
&lt;/rdf:List&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#first"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;first&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The first item in the subject RDF list.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#List"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/2000/01/rdf-schema#Resource"/&gt;
&lt;/rdf:Property&gt;

&lt;rdf:Property rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#rest"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;rest&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The rest of the subject RDF list after the first item.&lt;/rdfs:comment&gt;
  &lt;rdfs:domain rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#List"/&gt;
  &lt;rdfs:range rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#List"/&gt;
&lt;/rdf:Property&gt;

&lt;rdfs:Class rdf:about="http://www.w3.org/2000/01/rdf-schema#Datatype"&gt;
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/2000/01/rdf-schema#"/&gt;
  &lt;rdfs:label&gt;Datatype&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of RDF datatypes.&lt;/rdfs:comment&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Class"/&gt;
&lt;/rdfs:Class&gt;
	
&lt;rdfs:Datatype rdf:about="http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral"&gt;
  &lt;rdfs:subClassOf rdf:resource="http://www.w3.org/2000/01/rdf-schema#Literal"/&gt; 
  &lt;rdfs:isDefinedBy rdf:resource="http://www.w3.org/1999/02/22-rdf-syntax-ns#"/&gt;
  &lt;rdfs:label&gt;XMLLiteral&lt;/rdfs:label&gt;
  &lt;rdfs:comment&gt;The class of XML literal values.&lt;/rdfs:comment&gt;
&lt;/rdfs:Datatype&gt;

&lt;rdf:Description rdf:about="http://www.w3.org/2000/01/rdf-schema#"&gt;
  &lt;rdfs:seeAlso rdf:resource="http://www.w3.org/2000/01/rdf-schema-more"/&gt;
&lt;/rdf:Description&gt;

&lt;/rdf:RDF&gt;

        </pre>
      </td>
    </tr>
  </tbody>
</table>
<hr />

<div class="metadata">
<p><a href="metadata.rdf"><img border="0"
src="http://www.w3.org/RDF/icons/rdf_metadata_button.40"
alt="RDF/XML Metadata" /></a></p>
</div>
</body>
</html>