This appendix provides a brief introduction to RDF [12,18] and OWL [19,31], the primary modelling formalisms used in Semantic Web applications. The essential structure of RDF graphs is presented, followed by discussions of the concrete RDF syntax Turtle, RDFS, and the semantics of RDF. OWL, its semantics, and tractable OWL profiles are then presented.
Though they were both specifically developed for the Semantic Web and their development occurred in tandem, the motivations underlying RDF and OWL are different, and this is reflected in the syntax and semantics of each. RDF is intended to be simple and open, allowing users on the Web to make statements about resources. From the standpoint of logical expressivity, it is relatively limited. OWL, in contrast, is intended explicitly for the development of formal ontologies, and as such it has a more sophisticated logical syntax and semantics.
Both RDF and OWL are developed and maintained by the World Wide Web Consortium (W3C)
. Since this appendix provides only an incomplete overview of the formalisms, readers are encouraged to review the W3C specifications.
IOS Press, Inc.
6751 Tepper Drive
Clifton, VA 20124
Tel.: +1 703 830 6300
Fax: +1 703 830 2300 email@example.com
(Corporate matters and books only) IOS Press c/o Accucoms US, Inc.
For North America Sales and Customer Service
West Point Commons
Lansdale PA 19446
Tel.: +1 866 855 8967
Fax: +1 215 660 5042 firstname.lastname@example.org