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SKOS: Simple knowledge organisation for the Web

Introduction to SKOS

Page Contents

SKOS is an area of work developing specifications and standards to support the use of knowledge organisation systems (KOS) such as thesauri, classification schemes, subject heading systems and taxonomies within the framework of the Semantic Web.


SKOS provides a standard way to represent knowledge organisation systems using the Resource Description Framework (RDF). Encoding this information in RDF allows it to be passed between computer applications in an interoperable way.

Using RDF also allows knowledge organisation systems to be used in distributed, decentralised metadata applications. Decentralised metadata is becoming a typical scenario, where service providers want to add value to metadata harvested from multiple sources.

Status & Development

The SKOS Specifications are currently published as W3C Working Drafts, which means that they are work in progress.

The W3C Semantic Web Deployment Working Group (SWDWG) has recently taken responsibility for developing SKOS towards W3C Recommendation status by the first quarter of 2008. The SWDWG is currently undertaking a requirements gathering exercise, to provide a firm foundation for this work.

Community & Participation

All development work is carried out via the public-esw-thes@w3.org mailing list which is a completely open and publicly archived mailing list devoted to discussion of issues relating to knowledge organisation systems, information retrieval and the Semantic Web.

See also the development & participation page.

External Links

The following links may also be useful ...