The emergence of the World Wide Web (WWW) has brought exciting new possibilities for information access and electronic commerce. The WWW has become the largest distributed information repository ever created. Current estimates reveal that the Web currently contains approximately 3 billion static documents and is accessed by more than 500 million users worldwide [6]. Web content consists largely of distributed hypertext and hypermedia, accessible through keyword searching and link navigation. Simplicity is one of the web's greatest strengths and an important part of its popularity and growth. It is this simplicity that has fueled its wide adoption and exponential growth. However, it is this very simplicity that hinders the growth and exploitation of the web. The explosion in the range and quantity of Web content also reveals serious gaps in the hypertext paradigm [1]. It is increasingly difficult to locate required content via existing search and navigation methods ([1], [2], [3]). Finding the right information is often a challenge. Search engines can help find material containing specific words, but it is very easy to get lost in the huge amounts of irrelevant material. Selecting the relevant material from the million web pages displayed on the computer screen becomes a nightmare and is impractical manually, as it requires users to read through a large number of retrieved documents to extract the right information. Currently, it is hypothesized that the solution to this problem lies in the "invention" of machine-understandable semantics for all or part of the information on the WWW. The realization of such a Semantic Web [4] requires the development of techniques to express machine understanding...... middle of article ......o, F.van Harmelen, A Semantic Web Primer. The MIT Press, Massachusetts, 2004[3] HP Alesso, CF Smith, Thinking on the Web: Berners-Lee, Gödel and Turing. John Wiley and Sons, New Jersey-United States, 2009.[4] T. Berners-Lee, J. Hendler, O. Lassila, The Semantic Web, Scientific American Magazine, vol. 284, number 4, 2001, pp.34-43[5] TR Gruber, Towards principles for the design of ontologies used for knowledge sharing. Stanford Knowledge Systems Laboratory, 1993.[6] NPBui, S. Lee, T. Chung, Distributed ontology query on a grid environment. In: O. Gervasi and M. Gavrilova (Eds): ICCSA, 2007, Springer-Verlag Ltd, Berlin Heidelberg, 2007, pp.140-153..[7] W3C, OWL Web Ontology Language [online]. http://www.w3.org/TR/owl-features/, [May 2009].[8] Horrocks, I. Ontologies and the Semantic Web. Communications of the ACM, vol. 51, no. 12, 2008, p...58-67.