The Semantic Web Vision

Abstract. A number of techniques have been developed to facilitate powerful data retrieval on the Web and Semantic Web. Three categories of Web query languages can be distinguished, according to the format of the data they can retrieve: XML, RDF and Topic Maps. This ar-ticle introduces the spectrum of languages falling into these categories and summarises their salient aspects. The languages are introduced us-ing common sample data and query types. Key aspects of the query languages considered are stressed in a conclusion