OWL

OWL (Web Ontology Language) is a family of notations for expressing properties of an RDF ontology, which vary in expressive power. The simplest, OWLlite, can express whether instances of a class should have particlar properties (say that animals have a number of legs) or that a class is a sub-class of another (e.g. Dalmation is a kind of dog). More complex variants allow oen to declare, for example, that a class can only have a fixed set of instances, or to use levels of meta-modelling where classes can be treated as instances. In general, simpler variants are easier to deal with and check computationally, but are less expressive.

Used on pages 389, 428

Also known as web ontology language