The Semantic Web-on the respective Roles of XML and RDF

The next generation of the Web is often characterized as the “Semantic Web”: information will no longer only be intended for human readers, but also for processing by machines, enabling intelligent information services, personalized Web-sites, and semantically empowered search-engines. The Semantic Web requires interoperability on the semantic level. Semantic interoperability requires standards not only for the syntactic form of documents, but also for the semantic content. Proposals aiming at semantic interoperability are the results of recent W3C standardization efforts, notably XML/XML Schema and RDF/RDF Schema. In this paper, we make the following claims: • A further representation and inference layer is needed on top of the currently available layers of the WWW. • To establish such a layer, we propose a general method for encoding arbitrary ontology representation languages into RDF/RDF Schema. We illustrate the extension method by applying it to a particular ontology representation and inference language (OIL).