Ontology language
From Wikipedia, the free encyclopedia
In computer science and artificial intelligence, ontology languages are formal languages used to construct ontologies. They allow the encoding of knowledge about specific domains and often include reasoning rules that support the processing of that knowledge. Ontology languages are usually declarative languages, are almost always generalizations of frame languages, and are commonly based on either first-order logic or on description logic.
Contents
[edit] Classification
[edit] Traditional ontology languages
[edit] By syntax
[edit] Markup ontology languages
These languages use a markup scheme to encode knowledge, most commonly XML.
[edit] By structure
[edit] Frame-based
FLogic, OKBC, and KM, are completely or partially frame-based languages.
[edit] Description logic-based
Description logic provides an extension of frame languages, without going so far as to take the leap to first-order logic and support for arbitrary predicates. Examples include KL-ONE, RACER and OWL.
Gellish is an example of a combined ontology language and ontology that is description logic based. It distinguishes between the semantic differences among others of:
It also contains constructs to express queries and communicative intent.
[edit] First-order logic-based
CycL and KIF are examples of languages that support expressions in first-order logic, and, in particular, allow general predicates.

