Concept. Definition Concepts are the broad categories of objects (eg Castle) or an instance (eg The Tower of London). This group of pages is for all categories with emphasis on IT, and fortifications. Other specific ontologies such as Medicine and Biodiversity are separate with just a few cross links to other ontologies graphic has_type Artefact. has_type Building. has_type London_fortifications. has_type Military_structure. has_type Military_vehicle. has_type MS_access. has_type Southampton_history. has_type Star_fort. Other Concepts Concept_examples.       Vr.155, Dec 2010     Readme      ..