In the vision of Tim Berners-Lee the web is moving towards the Semantic Web in the near future, and further on to the Web of Reasoning. The first stages of the web were the Web of Documents (Web 1.0) and the Social Web (Web 2.0). The main instruments to realize the Semantic Web have already been developed: XML, RDF, etc. The first Semantic Web browsers are already operational. The Simple Knowledge Organization System (SKOS) guarantees that the vast knowledge hidden in the traditional instruments libraries used for indexing, i.e. subject headings, thesauri and classifications, can contribute to the realization of the Semantic Web.
Resource Description Framework ...