3. Ontologies

Originally, ontology was a branch of philosophy in which philosophers attempted to give a formal account of what exists. The philosophical term "ontology" comes from the ancient Greek ôn, onton, present participle of einai- and discourse, study, science – of logos (Encyclopédie Universalis, 2000).

At present, the term ontology is used in two ways, the first belonging to classical philosophy and the second, more recent, to the cognitive sciences. By convention, the notation ontology (with a capital O) is assigned to the field originating in philosophy, and ontology to the others.

Taken in its broadest sense, the term ontology can be defined as a theory or conception of reality. In computer science, an ontology is understood as a system of fundamental concepts that are represented in a form that can be interpreted by a computer.