Controlled vocabulary ⁽⁰⁾

The phrase controlled vocabulary is often used to denote that the concepts are managed in some way and that it is only possible to choose from amongst these concepts. A controlled vocabulary is a list of terms that are related to each other in some way: they should all be about the same thing. They are often also referred to as authority files as they represent an authoritative set of descriptions for a list of terms. The control aspect refers both to the fact that the terms available are specific and limited (for example, a folksonomy is not a controlled vocabulary, because it is not constrained to a particular set of terms) and also to the fact that such vocabularies have a set of house rules and management processes governing them.