In the context of
knowledge engineering, the term ontology
means a specification of a conceptualization. That is, an ontology is a
description of the concepts and relationships pertained to a specific area
of knowledge such as biology , ecology, marketing etc.
Ontologies establish a joint terminology between the members of
a community of interest. These members can be human or automated agents.
Several representation
languages and systems were developed for ontologies.
KIF-based Ontololingua,
Loom, F-Logic
are examples of representation languages based on First
Order Logic, but with different expressiveness and computational properties.
However, for applications on the web it is important to have a language with a
standardized syntax. The
World Wide Web Consortium (W3C)
has developed the
Extensible Markup Language (XML) which allows
information to be more accurately described using tags. As an example, the word
Algol on a web site might represent a computer language, a star or an
oceanographic research ship. The use of XML to provide metadata markup, such as
Description Logics (DL) are often used to back ontology languages with the reasoning power. For example, a tool such as OilEd uses DL reasoner for the analysis of DAML+OIL ontologies. DL syntax based on a set of convention which allows describing the common semantic constructs without any use of variables. All DL constructs allow simple and elegant graphic representation.
C 2003 S. Krivov Send your comments to skrivov@zoo.uvm.edu