Topic map

According to the definition by TopicMaps.Org Specification in XML Topic Maps (XTM) 1.0 (http://http://www.topicmaps.org/xtm/index.html) 1. A collection of topics, associations, and scopes that may exist in one of two forms:

  (1) a serialized interchange format (e.g. as a topic map document expressed in XTM syntax), or 
  (2) some application-internal form, as constrained by the XTM Processing Requirements defined in Annex F. 

2. The document element (<topicMap>) of a topic map document expressed using XTM syntax.