Description logic

Description logic is a family of formal languages for representing concepts, relationships, and individuals. Its reasoning procedures test consistency and derive classifications.

Concept: A description-logic expression that denotes a set of individuals. Concept descriptions build classes whose membership reasoners can test.
First-order logic: A formal system for reasoning about objects, properties, and relations using quantifiers and predicates. Description logics draw on predicate logic while restricting syntax to preserve useful reasoning properties.
Web Ontology Language: A family of Semantic Web languages for defining and sharing ontologies. OWL profiles use description logics to provide formal semantics and reasoning guarantees.
Semantic networks: Graph-based representations of concepts and their relationships, often used in artificial intelligence. Their limits in formal semantics helped motivate rigorously interpreted knowledge languages.
Datalog: A rule-based query language based on function-free logic programming. Datalog emphasizes recursive rules, unlike description logic's concept-and-role-centered modeling.
Role: A binary relation between individuals in a description logic knowledge base. Roles connect individuals and constrain how concepts relate.
Set theory: The mathematical study of sets, membership, and operations on collections. Concepts are interpreted as sets of individuals, giving the language its standard semantics.
Ontology: A formal specification of concepts and relations in a domain. Description logic supplies constructs for defining and classifying ontology terms.
KL-ONE: An early knowledge-representation system that introduced structured descriptions of concepts and roles. KL-ONE shaped the modeling ideas that developed into description logic.
Horn clause: A logical clause containing at most one positive literal. Horn logic supports efficient rule inference but does not directly provide the same ontology constructors.

Linked from 3 pages