The project behind the Friend of a Friend ontology for describing people and their social connections on the Semantic Web.

The FOAF Project created and maintains the Friend of a Friend (FOAF) ontology, a machine-readable RDF/OWL vocabulary for describing people, their activities, and their relationships. Started in 2000 by Dan Brickley and Libby Miller, FOAF was one of the earliest and most widely adopted Semantic Web vocabularies, enabling decentralized description of social networks without a centralized database. The FOAF vocabulary is used across linked data applications to represent personal profiles and social connections.