RDF Schema 1.1

RDF Schema 1.1
RDF Schema 1.1
W3C
Recommendation
25 February 2014
Document Status Update, 1 December 2023
The
Latest published version
link was fixed: it is intended to point to the latest version of the document for
this version of RDF
(i.e. RDF 1.1).
This version:
Latest published version:
Previous version:
Editors:
Dan Brickley
, Google
R.V. Guha
, Google
Previous Editors:
Brian McBride
Please check the
errata
for any errors or issues
reported since publication.
This document is also available in this non-normative format:
diff w.r.t. 2004 Recommendation
The English version of this specification is the only normative version. Non-normative
translations
may also be available.
2004-2014
W3C
MIT
ERCIM
Keio
Beihang
),

W3C
liability
trademark
and
document use
rules apply.
Abstract
RDF
Schema provides a data-modelling vocabulary for RDF data. RDF Schema
is an extension of the basic RDF vocabulary.
Status of This Document
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
W3C
technical reports index
at
This document is an edited version of the 2004 RDF
Schema Recommendation. The purpose of this revision is to make this
document available as part of the RDF 1.1 document set. Changes are
limited to errata, revised references, terminology updates, and adaptations to
the introduction. The title of the document was changed from "RDF
Vocabulary Description Language 1.0: RDF Schema" to "RDF Schema 1.1".
The technical content of the document is unchanged. Details of the changes
are listed in the
Changes
section.
Since the edits to this document do not constitute a technical
change the Director decided no new implementation report was
required.
This document was published by the
RDF Working Group
as a Recommendation.

If you wish to make comments regarding this document, please send them to
public-rdf-comments@w3.org
archives
).

All comments are welcome.
This document has been reviewed by
W3C
Members, by software developers, and by other
W3C
groups and interested parties, and is endorsed by the Director as a
W3C
Recommendation.
It is a stable document and may be used as reference material or cited from another
document.
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.
This document was produced by a group operating under the
5 February 2004
W3C
Patent
Policy
W3C
maintains a
public list of any patent
disclosures
made in connection with the deliverables of the group; that page also includes
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Essential
Claim(s)
must disclose the information in accordance with
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Table of Contents
1.
Introduction
2.
Classes
2.1
rdfs:Resource
2.2
rdfs:Class
2.3
rdfs:Literal
2.4
rdfs:Datatype
2.5
rdf:langString
2.6
rdf:HTML
2.7
rdf:XMLLiteral
2.8
rdf:Property
3.
Properties
3.1
rdfs:range
3.2
rdfs:domain
3.3
rdf:type
3.4
rdfs:subClassOf
3.5
rdfs:subPropertyOf
3.6
rdfs:label
3.7
rdfs:comment
4.
Using the Domain and Range vocabulary
5.
Other vocabulary
5.1
Container Classes and Properties
5.1.1
rdfs:Container
5.1.2
rdf:Bag
5.1.3
rdf:Seq
5.1.4
rdf:Alt
5.1.5
rdfs:ContainerMembershipProperty
5.1.6
rdfs:member
5.2
RDF Collections
5.2.1
rdf:List
5.2.2
rdf:first
5.2.3
rdf:rest
5.2.4
rdf:nil
5.3
Reification Vocabulary
5.3.1
rdf:Statement
5.3.2
rdf:subject
5.3.3
rdf:predicate
5.3.4
rdf:object
5.4
Utility Properties
5.4.1
rdfs:seeAlso
5.4.2
rdfs:isDefinedBy
5.4.3
rdf:value
6.
RDF Schema summary
6.1
RDF classes
6.2
RDF properties
A.
Acknowledgments
B.
Change since 2004 Recommendation
C.
References
C.1
Normative references
C.2
Informative references
1.
Introduction
RDF Schema provides a data-modelling vocabulary for RDF data.
It is complemented by several companion documents which
describe the basic concepts and abstract syntax of RDF
RDF11-CONCEPTS
], the formal semantics of RDF [
RDF11-MT
], and
various concrete syntaxes for RDF, such as Turtle [
TURTLE
],
TriG, [
TRIG
], and JSON-LD [
JSON-LD
]. The RDF Primer
RDF11-PRIMER
] provides an informal introduction and
examples of the use of the concepts specified in this document.
This document is intended to provide a clear specification of RDF
Schema to those who find the formal semantics
specification [
RDF11-MT
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.
RDF Schema is a
semantic
extension
of RDF. It provides mechanisms for describing groups of
related resources and the relationships between these resources. RDF
Schema is written in RDF
using the terms described in this document. These resources are used to
determine characteristics of other resources, such as the
domains
and
ranges
of properties.
The RDF Schema class and property system is similar to the type
systems of object-oriented programming languages such as Java. RDF
Schema differs from many such systems in that instead of defining a
class in
terms of the properties its instances may have, RDF Schema
describes properties in terms of the classes of
resource to which they apply. This is the role of the
domain
and
range
mechanisms described in this specification. For example, we could
define the
eg:author
property to have a domain of
eg:Document
and a range of
eg:Person
, whereas a classical object oriented system might
typically define a class
eg:Book
with an attribute called
eg:author
of type
eg:Person
. Using the RDF
approach, it is easy for others to subsequently define additional
properties with a domain of eg:
Document
or a range of
eg:Person
. 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 [
BERNERS-LEE98
].
This specification does not attempt to enumerate all the possible forms
of
representing the meaning of RDF
classes and properties. Instead, the RDF Schema 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 OWL [
OWL2-OVERVIEW
], 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.
The language defined in this specification consists of a collection of
RDF resources that can be used to describe other RDF resources in
application-specific RDF vocabularies. The core vocabulary is defined in
a namespace informally called
rdfs
here. That namespace is
identified by the IRI
and is conventionally associated with the prefix
rdfs:
. This
specification also uses the prefix
rdf:
to refer to the RDF namespace
For convenience and readability, this specification uses an abbreviated
form to represent IRIs. A name of the form prefix:suffix should be
interpreted as a IRI consisting of the IRI associated
with the prefix concatenated with the suffix.
2.
Classes
Resources may be divided into groups called classes. The members of a
class are known as
instances
of the class. Classes are
themselves
resources. They are often identified by
IRIs
and
may be described using RDF properties. The
rdf:type
property may be used to state that a
resource is an instance of a class.
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.
A class may be a member of its own class extension and may be an
instance of itself.
The group of resources that are RDF Schema classes is itself a class
called
rdfs:Class
If a class C is a
subclass
of a class C', then all instances
of C will
also be instances of C'. The
rdfs:subClassOf
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'.
The RDF Concepts and Abstract Syntax [
RDF11-CONCEPTS
] specification
defines the RDF concept of an
RDF
datatype
. All datatypes are classes. The instances of a class that
is a
datatype are the members of the value space of the datatype.
2.1
rdfs:Resource
All things described by RDF are called
resources
, and are
instances of the class
rdfs:Resource
. This is the class
of
everything. All other classes are
subclasses
of
this class.
rdfs:Resource
is an instance of
rdfs:Class
2.2
rdfs:Class
This is the class of resources that are RDF classes.
rdfs:Class
is an instance of
rdfs:Class.
2.3
rdfs:Literal
The class
rdfs:Literal
is the class of
literal
values such as strings and integers. Property values such as textual
strings are examples of RDF literals.
rdfs:Literal
is an instance of
rdfs:Class
rdfs:Literal is a
subclass
of
rdfs:Resource
2.4
rdfs:Datatype
rdfs:Datatype
is the class of datatypes. All instances
of
rdfs:Datatype
correspond to the
RDF
model
of a datatype
described in the RDF Concepts specification
RDF11-CONCEPTS
].
rdfs:Datatype
is
both an instance of and a
subclass
of
rdfs:Class
. Each instance of
rdfs:Datatype
is a
subclass
of rdfs:Literal.
2.5
rdf:langString
The class
rdf:langString
is the class of
language-tagged
string values
rdf:langString
is an instance of
rdfs:Datatype
and a
subclass
of
rdfs:Literal
2.6
rdf:HTML
This section is non-normative.
The class
rdf:HTML
is the class of
HTML
literal
values
rdf:HTML
is an instance of
rdfs:Datatype
and a
subclass
of
rdfs:Literal
2.7
rdf:XMLLiteral
This section is non-normative.
The class
rdf:XMLLiteral
is the class of
XML
literal
values
rdf:XMLLiteral
is an instance of
rdfs:Datatype
and a
subclass
of
rdfs:Literal
2.8
rdf:Property
rdf:Property
is the class of RDF properties.
rdf:Property
is an instance of
rdfs:Class
3.
Properties
The RDF Concepts and Abstract Syntax specification [
RDF11-CONCEPTS
describes the concept of an RDF property as a relation between subject
resources and object resources.
This specification defines the concept of subproperty. The
rdfs:subPropertyOf
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.
Note
The basic facilities provided by
rdfs:domain
and
rdfs:range
do not provide any
direct way to indicate property restrictions that are local to a class.
Although it is possible to combine use
rdfs:domain
and
rdfs:range
with sub-property
hierarchies, direct support for such declarations are provided by richer
Web Ontology languages such as OWL [
OWL2-OVERVIEW
].
3.1
rdfs:range
rdfs:range
is an instance of
rdf:Property
that is used to state that
the values of a property are instances of one or more classes.
The triple
P rdfs:range C
states that P is an instance of the class
rdf:Property
that C is an instance of the class
rdfs:Class
and that the resources denoted by the objects of triples whose
predicate is P are instances of the class C.
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
rdfs:range
properties.
The
rdfs:range
property can be applied to itself. The
rdfs:range of
rdfs:range
is the class
rdfs:Class
This states that any resource
that is the value of an
rdfs:range
property is an
instance of
rdfs:Class
The
rdfs:range
property is applied to properties. This
can be represented in RDF using the
rdfs:domain
property. The
rdfs:domain
of
rdfs:range
is
the class
rdf:Property
. This
states
that any resource with an
rdfs:range
property is an
instance of
rdf:Property
3.2
rdfs:domain
rdfs:domain
is an instance of
rdf:Property
that is used to state that
any resource that has a given property is an instance of one or more
classes.
A triple of the form:
P rdfs:domain C
states that P is an instance of the class
rdf:Property
that C is a instance of the class
rdfs:Class
and that the resources denoted by the subjects of triples whose
predicate is P are instances of the class C.
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
rdfs:domain
properties.
The
rdfs:domain
property may be applied to itself. The
rdfs:domain of
rdfs:domain
is the class
rdf:Property
This states that any
resource with an
rdfs:domain
property is an instance of
rdf:Property
The
rdfs:range
of
rdfs:domain
is the class
rdfs:Class
This states that any resource that is the value of an
rdfs:domain
property is an
instance of
rdfs:Class
3.3
rdf:type
rdf:type
is an instance of
rdf:Property
that is used to
state that a resource is an instance of a class.
A triple of the form:
R rdf:type C
states that C is an instance of
rdfs:Class
and R is an instance of C.
The
rdfs:domain
of
rdf:type
is
rdfs:Resource
The
rdfs:range
of rdf:type is
rdfs:Class
3.4
rdfs:subClassOf
The property
rdfs:subClassOf
is an instance of
rdf:Property
that is used to state
that all the instances of one class are instances of another.
A triple of the form:
C1 rdfs:subClassOf C2
states that C1 is an instance of
rdfs:Class
C2 is an instance of
rdfs:Class
and C1 is a
subclass
of C2. The
rdfs:subClassOf
property is transitive.
The
rdfs:domain
of
rdfs:subClassOf
is
rdfs:Class
The
rdfs:range
of
rdfs:subClassOf
is
rdfs:Class
3.5
rdfs:subPropertyOf
The property
rdfs:subPropertyOf
is an instance of
rdf:Property
that is used to state
that all resources related by one property are also related by
another.
A triple of the form:
P1 rdfs:subPropertyOf P2
states that P1 is an instance of
rdf:Property
P2 is an instance of
rdf:Property
and P1 is a
subproperty
of P2. The
rdfs:subPropertyOf
property is transitive.
The
rdfs:domain
of
rdfs:subPropertyOf
is
rdf:Property
The
rdfs:range
of
rdfs:subPropertyOf is
rdf:Property
3.6
rdfs:label
rdfs:label
is an instance of
rdf:Property
that may be used to provide a human-readable version of a resource's
name.
A triple of the form:
R rdfs:label L
states that L is a human readable label for R.
The
rdfs:domain
of
rdfs:label
is
rdfs:Resource
The
rdfs:range
of rdfs:label is
rdfs:Literal
Multilingual labels are supported using the
language
tagging
facility of RDF literals.
3.7
rdfs:comment
rdfs:comment
is an instance of
rdf:Property
that may be used to provide a human-readable description of a
resource.
A triple of the form:
R rdfs:comment L
states that L is a human readable description of R.
The
rdfs:domain
of
rdfs:comment
is
rdfs:Resource
The
rdfs:range
of rdfs:comment
is
rdfs:Literal
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.
Multilingual documentation is supported through use of the
language
tagging
facility of RDF literals.
4.
Using the Domain and Range vocabulary
This section is non-normative.
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.
RDF Schema 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
author
property
is used to
indicate resources that are instances of the class
Person
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.
RDF vocabularies can describe relationships between vocabulary items
from
multiple independently developed vocabularies. Since IRIs are used
to identify classes and properties on the Web, it is possible to create
new
properties that have a
domain
or
range
whose
value
is a class defined in another namespace.
5.
Other vocabulary
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.
5.1
Container Classes and Properties
This section is non-normative.
RDF containers are resources that are used to represent collections.
The same resource may appear in a container more than
once. Unlike containment in the physical world, a container may be
contained in itself.
Three different kinds of container are defined. Whilst the formal
semantics [
RDF11-MT
] 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
container
membership properties
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.
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.
RDF containers are defined by the following classes and properties.
5.1.1
rdfs:Container
The
rdfs:Container
class is a super-class of the RDF
Container classes, i.e.
rdf:Bag
rdf:Seq
rdf:Alt
5.1.2
rdf:Bag
The
rdf:Bag
class is the class of RDF 'Bag'
containers. It is
subclass
of
rdfs:Container
Whilst formally it is no
different from an
rdf:Seq
or an
rdf:Alt
, the
rdf:Bag
class is used
conventionally to indicate to a human reader that the container is
intended
to be unordered.
5.1.3
rdf:Seq
The
rdf:Seq
class is the class of RDF 'Sequence'
containers.
It is a
subclass
of
rdfs:Container
Whilst formally it is no
different from an
rdf:Bag
or an
rdf:Alt
, the
rdf:Seq
class is used
conventionally to indicate to a human reader that the numerical
ordering of
the
container membership
properties
of the container is intended to be significant.
5.1.4
rdf:Alt
The
rdf:Alt
class is the class of RDF 'Alternative'
containers. It is a
subclass
of
rdfs:Container
. Whilst formally
it is no
different from an
rdf:Seq
or an
rdf:Bag
, the
rdf:Alt
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
rdf:_1
property, is the
default choice.
5.1.5
rdfs:ContainerMembershipProperty
The
rdfs:ContainerMembershipProperty
class has as
instances
the properties
rdf:_1, rdf:_2, rdf:_3 ...
that are
used to state
that a resource is a member of a container.
rdfs:ContainerMembershipProperty
is a
subclass
of
rdf:Property
. Each
instance of
rdfs:ContainerMembershipProperty
is an
rdfs:subPropertyOf
the
rdfs:member
property.
Given a container C, a triple of the form:
C rdf:_nnn O
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.
Container membership properties may be applied to resources other
than containers.
5.1.6
rdfs:member
rdfs:member
is an instance of
rdf:Property
that is a super-property of all
the container membership properties i.e. each container membership
property
has an
rdfs:subPropertyOf
relationship to the property
rdfs:member
The
rdfs:domain
of
rdfs:member
is
rdfs:Resource
The
rdfs:range
of
rdfs:member
is
rdfs:Resource
5.2
RDF Collections
This section is non-normative.
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.
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
shorthand
notation
in the Turtle syntax specification for representing
collections.
Note
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.
5.2.1
rdf:List
rdf:List
is an instance of
rdfs:Class
that can be used to build descriptions of lists and other list-like
structures.
5.2.2
rdf:first
rdf:first
is an instance of
rdf:Property
that can be used to build descriptions of lists and other list-like
structures.
A triple of the form:
L rdf:first O
states that there is a first-element relationship between L and O.
The
rdfs:domain
of
rdf:first
is
rdf:List
. The
rdfs:range
of
rdf:first
is
rdfs:Resource
5.2.3
rdf:rest
rdf:rest
is an instance of
rdf:Property
that can be used to build descriptions of lists and other list-like
structures.
A triple of the form:
L rdf:rest O
states that there is a rest-of-list relationship between L and O.
The
rdfs:domain
of
rdf:rest
is
rdf:List
. The
rdfs:range
of
rdf:rest
is
rdf:List
5.2.4
rdf:nil
The resource
rdf:nil
is an instance of
rdf:List
that can be used to represent an empty list or other list-like
structure.
A triple of the form:
L rdf:rest rdf:nil
states that L is an instance of
rdf:List
that has one item; that item can be indicated using the
rdf:first
property.
5.3
Reification Vocabulary
This section is non-normative.
5.3.1
rdf:Statement
rdf:Statement
is an instance of
rdfs:Class.
It is intended to represent the class of RDF statements. An RDF
statement is the statement made by a token of an RDF triple. The
subject of an RDF statement is the instance of
rdfs:Resource
identified by the subject of the triple. The predicate of an RDF
statement is the instance of
rdf:Property
identified by the predicate of the triple. The object of an RDF
statement is the instance of
rdfs:Resource
identified by the object of the triple.
rdf:Statement
is in the domain of the properties
rdf:predicate
rdf:subject
and
rdf:object
. Different
individual
rdf:Statement
instances may have the same
values for their
rdf:predicate
rdf:subject
and
rdf:object
properties.
5.3.2
rdf:subject
rdf:subject
is an instance of
rdf:Property
that is used to state the
subject of a statement.
A triple of the form:
S rdf:subject R
states that S is an instance of
rdf:Statement
and that the subject of S is
R.
The
rdfs:domain
of
rdf:subject
is
rdf:Statement
. The
rdfs:range
of
rdf:subject
is
rdfs:Resource
5.3.3
rdf:predicate
rdf:predicate is an instance of
rdf:Property
that is used to state the
predicate of a statement.
A triple of the form:
S rdf:predicate P
states that S is an instance of
rdf:Statement
that P is an instance of
rdf:Property
and that the
predicate
of S is P.
The
rdfs:domain
of
rdf:predicate
is
rdf:Statement
and the
rdfs:range
is
rdfs:Resource
5.3.4
rdf:object
rdf:object is an instance of
rdf:Property
that is used to state the
object of a statement.
A triple of the form:
S rdf:object O
states that S is an instance of
rdf:Statement
and that the object of S is
O.
The
rdfs:domain
of
rdf:object
is
rdf:Statement
The
rdfs:range
of
rdf:object
is
rdfs:Resource
5.4
Utility Properties
The following utility classes and properties are defined in the RDF
core
namespaces.
5.4.1
rdfs:seeAlso
rdfs:seeAlso
is an instance of
rdf:Property
that is used to indicate a
resource that might provide additional information about the subject
resource.
A triple of the form:
S rdfs:seeAlso O
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.
The
rdfs:domain
of
rdfs:seeAlso
is
rdfs:Resource
The
rdfs:range
of
rdfs:seeAlso
is
rdfs:Resource
5.4.2
rdfs:isDefinedBy
rdfs:isDefinedBy
is an instance of
rdf:Property
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.
A triple of the form:
S rdfs:isDefinedBy O
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.
rdfs:isDefinedBy
is a
subproperty
of
rdfs:seeAlso
The
rdfs:domain
of
rdfs:isDefinedBy
is
rdfs:Resource
The
rdfs:range
of
rdfs:isDefinedBy
is
rdfs:Resource
5.4.3
rdf:value
rdf:value
is an instance of
rdf:Property
that may be used in
describing structured values.
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 example below:
Example 1

[
rdf:value 2.4 ;

] .
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.
The
rdfs:domain
of
rdf:value
is
rdfs:Resource
The
rdfs:range
of
rdf:value
is
rdfs:Resource
6.
RDF Schema summary
This section is non-normative.
The tables in this section provide an overview of the RDF Schema vocabulary.
6.1
RDF classes
Class name
comment
rdfs:Resource
The class resource, everything.
rdfs:Literal
The class of literal values, e.g. textual strings and
integers.
rdf:langString
The class of language-tagged string literal values.
rdf:HTML
The class of HTML literal values.
rdf:XMLLiteral
The class of XML literal values.
rdfs:Class
The class of classes.
rdf:Property
The class of RDF properties.
rdfs:Datatype
The class of RDF datatypes.
rdf:Statement
The class of RDF statements.
rdf:Bag
The class of unordered containers.
rdf:Seq
The class of ordered containers.
rdf:Alt
The class of containers of alternatives.
rdfs:Container
The class of RDF containers.
rdfs:ContainerMembershipProperty
The class of container membership properties, rdf:_1, rdf:_2,
..., all of which are sub-properties of 'member'.
rdf:List
The class of RDF Lists.
6.2
RDF properties
Property name
comment
domain
range
rdf:type
The subject is an instance of a class.
rdfs:Resource
rdfs:Class
rdfs:subClassOf
The subject is a subclass of a class.
rdfs:Class
rdfs:Class
rdfs:subPropertyOf
The subject is a subproperty of a property.
rdf:Property
rdf:Property
rdfs:domain
A domain of the subject property.
rdf:Property
rdfs:Class
rdfs:range
A range of the subject property.
rdf:Property
rdfs:Class
rdfs:label
A human-readable name for the subject.
rdfs:Resource
rdfs:Literal
rdfs:comment
A description of the subject resource.
rdfs:Resource
rdfs:Literal
rdfs:member
A member of the subject resource.
rdfs:Resource
rdfs:Resource
rdf:first
The first item in the subject RDF list.
rdf:List
rdfs:Resource
rdf:rest
The rest of the subject RDF list after the first item.
rdf:List
rdf:List
rdfs:seeAlso
Further information about the subject resource.
rdfs:Resource
rdfs:Resource
rdfs:isDefinedBy
The definition of the subject resource.
rdfs:Resource
rdfs:Resource
rdf:value
Idiomatic property used for structured values.
rdfs:Resource
rdfs:Resource
rdf:subject
The subject of the subject RDF statement.
rdf:Statement
rdfs:Resource
rdf:predicate
The predicate of the subject RDF statement.
rdf:Statement
rdfs:Resource
rdf:object
The object of the subject RDF statement.
rdf:Statement
rdfs:Resource
In addition to these classes and properties, RDF also uses properties
called
rdf:_1
rdf:_2
rdf:_3
...
etc.,
each of which is both a sub-property of
rdfs:member
and
an
instance of the class
rdfs:ContainerMembershipProperty
There is
also an instance of
rdf:List
called
rdf:nil
that is
an empty
rdf:List
A.
Acknowledgments
This section is non-normative.
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
RDF Core Working Group
members
, and
from
implementation feedback from many members of the
RDF
Interest Group
. In
2013-2014 Guus Schreiber edited this document on behalf of the
RDF
Working Group
to bring it in line with the RDF 1.1 specifications.
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.
The original RDF Schema Working Group membership included:
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.)
B.
Change since 2004 Recommendation
This section is non-normative.
Changes for RDF 1.1 Recommendation
No changes.
Changes for RDF 1.1 Proposed Edited Recommendation
Conversion to ReSpec, including formatting of examples and notes.
References to RDF 1.0 documents where appropriate
replaced by references to RDF 1.1 documents.
Replaced the term "URI Reference" with the term "IRI".
Removed discussion about distinction between plain and typed
literals, as this distinction is absent in RDF 1.1 and has no
technical bearing on RDF Schema.
Removed the introductory paragraph of Sec.
"Reification
Vocabulary"
, as this discussion is not related to the
technical content and is irrelevant and confusing now.
Update of affiliation of the editors.
Added RDF WG to the Acknowledgements section.
Renamed the document from "RDF Vocabulary Description Language
1.0: RDF Schema" to "RDF Schema 1.1", as the term Vocabulary
Description Language has led to confusion.
Three paragraphs of the Introduction were left out. These
paragraphs described the things that RDF Schema does not do and are
now much less relevant than in 2004.
Added the datatypes
rdf:langString
and
rdf:HTML
Removed Appendix "RDF Schema in RDF/XML". It was informative, but
now out of date, in terms of content and in terms of
syntax.
Marked
rdf:HTML
and
rdf:XMLLiteral
as non-normative.
Removed references to 2004 Primer from Secs. 5.1, 5.2
and 5.4.3. In the latter case the example referred to was
moved into this document for readability purposes.
C.
References
C.1
Normative references
[JSON-LD]
Manu Sporny, Gregg Kellogg, Markus Lanthaler, Editors.
JSON-LD 1.0
. 16 January 2014. W3C Recommendation. URL:
[RDF11-CONCEPTS]
Richard Cyganiak, David Wood, Markus Lanthaler.
RDF 1.1 Concepts and Abstract Syntax.
W3C Recommendation, 25 February 2014. URL:
. The latest edition is available at
[RDF11-MT]
Patrick J. Hayes, Peter F. Patel-Schneider.
RDF 1.1 Semantics.
W3C Recommendation, 25 February 2014. URL:
. The latest edition is available at
[TRIG]
Gavin Carothers, Andy Seaborne.
TriG: RDF Dataset Language
. W3C Recommendation, 25 February 2014. URL:
. The latest edition is available at
[TURTLE]
Eric Prud'hommeaux, Gavin Carothers.
RDF 1.1 Turtle: Terse RDF Triple Language.
W3C Recommendation, 25 February 2014. URL:
. The latest edition is available at
C.2
Informative references
[BERNERS-LEE98]
Tim Berners-Lee.
What the Semantic Web can represent
. 1998. URI:
[OWL2-OVERVIEW]
W3C OWL Working Group.
OWL 2 Web Ontology Language Document Overview (Second Edition)
. 11 December 2012. W3C Recommendation. URL:
[RDF11-PRIMER]
Guus Schreiber, Yves Raimond.
RDF 1.1 Primer
. W3C Working Group Note, 25 February 2014. The latest version is available at