A review of Ontology concept in semantic web

Nowadays ontologies are applied to improve the meaning of data in semantic web. The necessity of ontology engineering is due to providing an appropriate frame to define concepts and their relations with less ambiguity. The present paper tries to give theoretically a brief and exhaustive view to ontology and its evolution because background literature provides an explicit and better perception in research of this filed.
Method/ aproach: The paper reviews and discusses the concept of ontology.

Ontologies are as an extended network of relations between elements and concepts to represent knowledge in information systems and semantic web. As a new approach in knowledge engineering ontologies are important in artificial intelligence. By making ontologies the conceptual structure among cocepts is extracted and presented in an explicit formalized format.

Ontologies cause concept processing to be provided in different levels of human-machine interaction and are applied to knowledge sharing and representation. By designing and applying ontology to knowledge-based systems it is possible to resolve some existing problems in some fields such as retrieval systems, automatic reasoning process, designing intelligent systems and knowledge engineering.