The State of the Art: Ontology Web-Based Languages: XML Based
  Many formal languages have been proposed to express or represent Ontologies,
including RDF, RDFS, DAML+OIL and OWL. Most of these languages are based on XML
syntax, but with various terminologies and expressiveness. Therefore, choosing
a language for building an Ontology is the main step. The main point of
choosing language to represent Ontology is based mainly on what the Ontology
will represent or be used for. That language should have a range of quality
support features such as ease of use, expressive power, compatibility, sharing
and versioning, internationalisation. This is because different kinds of
knowledge-based applications need different language features. The main
objective of these languages is to add semantics to the existing information on
the web. The aims of this paper is to provide a good knowledge of existing
language and understanding of these languages and how could be used.
