Getty Research Institute Art & Architecture Thesaurus (AAT) OnlineThe Art & Architecture Thesaurus ® (AAT), the Getty Thesaurus of Geographic Names ® (TGN), the Union List of Artist Names ® (ULAN), the Cultural Objects Name Authority ® (CONA), and the Iconography Authority ™(IA) are structured resources that can be used to improve access to information for art, architecture, and other material culture. The Getty Vocabularies are not simple 'value vocabularies'; they are unique knowledge bases in themselves. Through rich metadata and links, the Getty Vocabularies provide powerful conduits for knowledge creation, complex research, and discovery for digital art history and related disciplines.