Handbook on Ontologies

Part of the series International Handbooks on Information Systems pp 1-17


What Is an Ontology?

  • Nicola GuarinoAffiliated withITSC-CNR, Laboratory for Applied Ontology Email author 
  • , Daniel OberleAffiliated withSAP Research, CEC Karlsruhe
  • , Steffen StaabAffiliated withUniversity of Koblenz-Landau, ISWeb

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The word “ontology” is used with different senses in different communities. The most radical difference is perhaps between the philosophical sense, which has of course a well-established tradition, and the computational sense, which emerged in the recent years in the knowledge engineering community, starting from an early informal definition of (computational) ontologies as “explicit specifications of conceptualizations”. In this paper we shall revisit the previous attempts to clarify and formalize such original definition, providing a detailed account of the notions of conceptualization and explicit specification, while discussing at the same time the importance of shared explicit specifications.