he W3C Web Ontology Language (OWL) is a Semantic Web language designed to represent rich and complex knowledge about things, groups of things, and relations between things.
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 SKOS API is a Java interface and implementation for the W3C Simple Knowledge Organisation System SKOS. For more information about SKOS see here. An implementation of the SKOS API is provided which uses the OWL 2 API, at present you will need to obtain the OWL API seperately from the OWL 2 website. [UPDATE 12-09-2011] The current release of the SKOS API has been deprecated, a new version_3 developer branch is available in the SVN repository that works with the latest OWL API v3.
For more information please contact the user group at skos-dev@googlegroups.com
The SKOS API is open source and is available under the LGPL License
The SKOS API includes the following components:
An API for the major SKOS constructs and an efficient in-memory reference implementation based on the OWL 2 API
Abstract data model for working for SKOS that avoids commitment to any of the concrete syntaxes, such as RDF
RDF/XML parser and writer
OWL/XML parser and writer
OWL Functional Syntax parser and writer
Turtle parser and writer
Support for extending the underlying SKOS data model via the OWL 2 API
Support for integration with reasoners such as Pellet and FaCT++
Range of convenience methods for working with SKOS
M. van Assem, A. Gangemi, and G. Schreiber. In Proceedings of the Fifth International Conference on Language Resources and Evaluation (LREC'06), (2006)