OWL 2 Web Ontology Language
Quick Reference Guide
W3C Editor's Draft 21 May 2009
- This version:
- http://www.w3.org/2007/OWL/draft/ED-owl2-quick-reference-20090521/
- Latest editor's draft:
- http://www.w3.org/2007/OWL/draft/owl2-quick-reference/
- Previous version:
- http://www.w3.org/2007/OWL/draft/ED-owl2-quick-reference-20090421/ (color-coded diff)
- Authors:
- Jie Bao, Rensselaer Polytechnic Institute
- Elisa F. Kendall, Sandpiper Software, Inc.
- Deborah L. McGuinness, Rensselaer Polytechnic Institute
- Peter F. Patel-Schneider, Bell Labs Research, Alcatel-Lucent
- Contributors:
- Li Ding, Rensselaer Polytechnic Institute
- Ankesh Khandelwal, Rensselaer Polytechnic Institute
This document is also available in these non-normative formats: PDF version.
Copyright © 2009 W3C® (MIT, ERCIM, Keio), All Rights Reserved. W3C liability, trademark and document use rules apply.
The OWL 2 Web Ontology Language, informally OWL 2, is an ontology language for the Semantic Web with formally defined meaning. OWL 2 ontologies provide classes, properties, individuals, and data values and are stored as Semantic Web documents. OWL 2 ontologies can be used along with information written in RDF, and OWL 2 ontologies themselves are primarily exchanged as RDF documents. The OWL 2
Document Overview describes the overall state of OWL 2, and should be read before other OWL 2 documents.
May Be Superseded
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 http://www.w3.org/TR/.
Summary of Changes
This Working Draft has undergone significant presentation
changes and a reorganization.
Last
Call
The Working Group believes it has completed its design
work for the technologies specified this document, so this
is a "Last Call" draft. The design is not expected to
change significantly, going forward, and now is the key
time for external review, before the implementation
phase.
Please Comment By 9 July 2009
The OWL Working Group seeks
public feedback on this Working Draft. Please send your
comments to public-owl-comments@w3.org (public archive). If possible, please offer
specific changes to the text that would address your
concern. You may also wish to check the Wiki
Version of this document and see if the relevant text has already
been updated.
No Endorsement
Publication as a Working Draft does not imply endorsement by the W3C Membership. This is a draft document and may be updated, replaced or obsoleted by other documents at any time. It is inappropriate to cite this document as other than work in progress.
Patents
This document was produced by a group operating under the 5 February 2004 W3C Patent Policy. This document is informative only. W3C maintains a public list of any patent disclosures made in connection with the deliverables of the group; that page also includes instructions for disclosing a patent. An individual who has actual knowledge of a patent which the individual believes contains Essential Claim(s) must disclose the information in accordance with section 6 of the W3C Patent Policy.
Editor's Note: To do list:
- Make a new pdf print version when the guide is finalized. (pdf) (wiki file)
1 Names, Prefixes, and Notation
Names in OWL 2 are IRIs, often written in a shorthand prefix:local_name, where prefix: is a prefix name that expands to an IRI, and local_name is the remainder of the name.
The standard prefix names in OWL 2 are:
| Prefix Name | Expansion
|
| rdf: | http://www.w3.org/1999/02/22-rdf-syntax-ns#
|
| rdfs: | http://www.w3.org/2000/01/rdf-schema#
|
| owl: | http://www.w3.org/2002/07/owl#
|
| xsd: | http://www.w3.org/2001/XMLSchema#
|
We use the following notation conventions: 'C' is a class expression; 'CN' is a class name; 'D' is a data range; 'DN' is a datatype name; 'P' is an object property expression; 'PN' is an object property name; 'R' is a data property; 'A' is an annotation property; 'a' is an individual; 'aN' is an individual name; '_:a' is an anonymous individual (a blank node label); 'v' is a literal; 'n' is a non-negative integer (as a shorthand for "n"^^xsd:nonNegativeInteger); 'f' is a facet; 'ON' is an ontology name; 'U' is an IRI; 's' is an IRI (including a named ontology, class, datatype, property or individual), or an anonymous individual; 't' is an IRI, an anonymous individual, or a literal; and 'p' is a prefix name.
In the RDF syntax, '_:x' is a blank node and '(a1 … an)' is an RDF list.
All of the above can have subscripts.
2 OWL 2 constructs and axioms
For an OWL 2 DL ontology, there are some global restrictions on axioms.
In the following tables the first column provides links to the Primer (if applicable) and the 2nd column provides links to the Functional Syntax.
Predefined and Named Classes
| Language Feature | Functional Syntax | RDF Syntax
|
| named class | CN | CN
|
| universal class | owl:Thing | owl:Thing
|
| empty class | owl:Nothing | owl:Nothing
|
Boolean Connectives and Enumeration of Individuals
Object Property Restrictions
Data Property Restrictions
| Language Feature | Functional Syntax | RDF Syntax
|
| universal | DataAllValuesFrom(R D) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:allValuesFrom D.
|
| existential | DataSomeValuesFrom(R D) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:someValuesFrom D.
|
| literal value | DataHasValue(R v) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:hasValue v.
|
| exact cardinality | DataExactCardinality(n R)
| _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:cardinality n.
|
| qualified exact cardinality | DataExactCardinality(n R D)
| _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:qualifiedCardinality n.
_:x owl:onDataRange D.
|
| maximum cardinality | DataMaxCardinality(n R) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:maxCardinality n.
|
| qualified maximum cardinality | DataMaxCardinality(n R D) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:maxQualifiedCardinality n.
_:x owl:onDataRange D.
|
| minimum cardinality | DataMinCardinality(n R) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:minCardinality n.
|
| qualified minimum cardinality | DataMinCardinality(n R D) | _:x rdf:type owl:Restriction.
_:x owl:onProperty R.
_:x owl:minQualifiedCardinality n.
_:x owl:onDataRange D.
|
Restrictions Using n-ary Data Range
In the following table 'Dn' is an n-ary data range.
| Language Feature | Functional Syntax | RDF Syntax
|
| n-ary universal | DataAllValuesFrom(R1 … Rn Dn) | _:x rdf:type owl:Restriction.
_:x owl:onProperties ( R1 … Rn ).
_:x owl:allValuesFrom Dn.
|
| n-ary existential | DataSomeValuesFrom(R1 … Rn Dn) | _:x rdf:type owl:Restriction.
_:x owl:onProperties ( R1 … Rn).
_:x owl:someValuesFrom Dn.
|
2.2 Properties
Object Property Expressions
Data Property Expressions
2.3 Individuals & Literals
2.4 Data Ranges
Data Range Expressions
2.5 Axioms
Class Expression Axioms
Object Property Axioms
Data Property Axioms
Datatype Definitions
Assertions
Keys
| Language Feature | Functional Syntax | RDF Syntax
|
| Key | HasKey(C (P1 … Pm) (R1 … Rn) ) | C owl:hasKey (P1 … Pm R1 … Rn).
|
2.6 Declarations
2.7 Annotations
Annotations
Annotation Properties
Annotation Axioms
2.8 Ontologies
Ontologies
| Language Feature | Functional Syntax | RDF Syntax
|
OWL ontology
(importing) |
Ontology([ON [U]]
Import(ON1)...
Annotation(A t)
...
) | ON rdf:type owl:Ontology.
[ON owl:versionIRI U.]
ON owl:imports ON1. ...
ON A t.
...
|
| prefix declaration | Prefix(p=U) | @prefix p U.
|
Note: in the RDF syntax _:x is used if there is no ontology name.
3 Built-in Datatypes and Facets
3.1 Built-in Datatypes
- Note: owl:rational and rdf:XMLLiteral are at Risk in OWL 2.
3.2 Facets
| Facet | Value | Applicable Datatypes | Explanation
|
xsd:minInclusive
xsd:maxInclusive
xsd:minExclusive
xsd:maxExclusive
| literal in the corresponding datatype
| Numbers,
Time Instants
| Restricts the value-space to greater than (equal to) or lesser than (equal to) a value
|
xsd:minLength
xsd:maxLength
xsd:length
| Non-negative integer
| Strings,
Binary Data,
IRIs
| Restricts the value-space based on the
lengths of the literals
|
| xsd:pattern
| xsd:string literal as a regular expression
| Strings,
IRIs
| Restricts the value space to literals that> match the regular expression
|
| rdf:langRange
| xsd:string literal as a regular expression
| rdf:text
| Restricts the value space to literals with language tags that match the regular expression
|
4 Appendix
4.1 New Features in OWL 2
| Class Expressions |
|
| Class Axioms |
|
| Property Expressions |
|
| Property Axioms |
|
| Data Ranges |
|
| Assertions |
|
| Annotation |
|
| Extra Built-in Datatypes |
- owl:rational, owl:real, xsd:dateTimeStamp, rdf:text
|
| Others |
|
4.2 Deprecated Vocabulary in OWL 2
The following vocabulary is provided in OWL 1 but not encouraged in OWL 2.
| OWL 1 Vocabulary | Status in OWL 2
|
| owl:DataRange | replaced by rdfs:Datatype
|
| owl:distinctMembers | replaced by owl:members
|
5 Acknowledgments
The starting point for the development of OWL 2 was the OWL1.1 member submission, itself a result of user and developer feedback, and in particular of information gathered during the OWL Experiences and Directions (OWLED) Workshop series. The working group also considered postponed issues from the WebOnt Working Group.
This document has been produced by the OWL Working Group (see below), and its contents reflect extensive discussions within the Working Group as a whole.
The editors extend special thanks to
Bernardo Cuenca Grau (Oxford University),
Christine Golbreich (Université de Versailles St-Quentin and LIRMM),
Ivan Herman (W3C/ERCIM), and
Bijan Parsia (University of Manchester)
for their thorough reviews.
The regular attendees at meetings of the OWL Working Group at the time of publication of this document were:
Jie Bao (RPI),
Diego Calvanese (Free University of Bozen-Bolzano),
Bernardo Cuenca Grau (Oxford University),
Martin Dzbor (Open University),
Achille Fokoue (IBM Corporation),
Christine Golbreich (Université de Versailles St-Quentin and LIRMM),
Sandro Hawke (W3C/MIT),
Ivan Herman (W3C/ERCIM),
Rinke Hoekstra (University of Amsterdam),
Ian Horrocks (Oxford University),
Elisa Kendall (Sandpiper Software),
Markus Krötzsch (FZI),
Carsten Lutz (Universität Bremen),
Deborah L. McGuinness (RPI),
Boris Motik (Oxford University),
Jeff Pan (University of Aberdeen),
Bijan Parsia (University of Manchester),
Peter F. Patel-Schneider (Bell Labs Research, Alcatel-Lucent),
Alan Ruttenberg (Science Commons),
Uli Sattler (University of Manchester),
Michael Schneider (FZI),
Mike Smith (Clark & Parsia),
Evan Wallace (NIST), and
Zhe Wu (Oracle Corporation).
We would also like to thank past members of the working group:
Jeremy Carroll,
Jim Hendler,
Vipul Kashyap.