Created on Feb. 10, 2013, 2:02 a.m. by Hevok & updated by Hevok on May 2, 2013, 4:38 p.m.

Ontology in a philosophical Context is Study of the Nature of Being, existence or reality in general, as well as of the basic Categories of being and their Relations.

Ontology is singular because it is a study. In Computer Science the Term refers to Knowledge Representation. Therefore, there can be more than one Ontology and thus it can be plural, hence there are Ontologies.

In an Information Technology Context an Ontology is a Model for describing the World that consists of a set of Types, Properties, and Relationship Types.

Ontologies are explicit formal Specifications of the Terms in the Domain and Relations among them [Gruber 1993].

Ontologies on the Web range from large Taxonomies categorizing Web Sites to Categorization of single Entities and their Features.

A single Ontology defines a common Vocabulary for Researchers who need to share Information in a Domain. It includes machine-interpretable Definitions of basic Concepts in the Domain and Relations among them.

The development of an Ontology allows to:

For the Semantic Web and Linked Data the Models are based on the use of RDF, RDFS, and OWL which are used to describe the Types, Properties, and Relationship Types.

Ontologies are also commonly known as RDF "Vocabolaries".

Ontology are Collections of Informations. The term Ontology is co-opted by Artificial Intelligence and Web Researchers, in which an Ontology is a Document or File that formally defines the Relations among Terms. The most typical kind of Ontology for the Web has a Taxonomy and a set of Inference Rules.


Gruber, T.R. (1993). A Translation Approach to Portable Ontology Specification. Knowledge Acquisition 5: 199-220.


Tags: categories, concepts, modeling, vocabolaries, models
Categories: Concept
Parent: Semantic
Children: Components and Models of Ontologies, Ontology Category, Ontology Mapping, Ontology Type, Representing Ontologies

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Ontologies -is plural of-> Ontology

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