The subfield of artificial intelligence concerned with designing and using systems for storing knowledge - facts and rules about some subject.
A body of formally represented knowledge is based on a conceptualisation - an abstract view of the world that we wish to represent. In order to manipulate this knowledge we must specify how the abstract conceptualisation is represented as a concrete data structure. An ontology is an explicit specification of a conceptualisation.
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Nearby terms: knowledge level « Knowledge Management System « Knowledge Query and Manipulation Language « knowledge representation » Knowledge Sharing Effort » Knowledge Systems Laboratory » Known Lazy Bastard