What is a “Controlled Vocabulary”
“The greatest problem of today is how to teach people to ignore the irrelevant, how to refuse to know things, before they are suffocated. For too many facts are as bad as none at all.” (W.H. Auden)
Similarly, there are too many ways of expressing or explaining the topic of a document.
Controlled vocabularies are sets of Rules for topic identification and indexing, and a THESAURUS, which consists of “lead-in vocabulary” and an limited and selective “Indexing Language” sometimes with special coding or structures.