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What is an ontology?

In philosophy,

  • ontology is the study of being or existence. It seeks to describe or posit the basic categories and relationships of being or existence to define entities and types of entities.1)

In modern computer science and information science basic definitions consider an ontology to be:

  • a data model that represents a set of concepts within a domain, and the relationships between those concepts2)
  • an explicit specification of a conceptualization.3)
  • an explicit formal specification of the terms in the domain and relations among them4)

In more details, an ontology can be described as:

  • a formal explicit description of concepts or classes in a domain of discourse, with
  • properties of each concept describing various features and attributes of the concept (slots, roles or properties), and
  • restrictions on concept slots (facets or role restrictions).5)

An ontology has the following properties:6)

  • it is used to reason about the objects in a domain;
  • specifies the classes of concepts and their relations at a higher level than relevant to the domain;
  • captures the intrinsic conceptual structure of a domain;
  • forms the hearth of the knowledge representation within a domain.

Why do we need an ontology?

An ontology can be used to:7)

  • share common understanding of the structure of information among people or software agents
  • enable reuse of domain knowledge
  • make domain assumptions explicit
  • separate domain knowledge from the operational knowledge
  • analyze domain knowledge

So how do I create an ontology?

You can follow this brief guide. even instance), or domain (the domain of a slot contains all the classes with this slot) and range (if a slot is an instance, its range are considered to be all the classes the instance can be originating from) of a slot.

  1. Create instances -
misc/ontology.1317897110.txt.gz · Last modified: 2012/01/12 11:42 (external edit)