Answered By: APUS Librarians Last Updated: Nov 26, 2018 Views: 4418
A controlled vocabulary is a list of standardized subject headings used by catalogers and database indexers to describe what a source (e.g. an article or book) is about. These subject headings may also be referred to as subject terms, preferred terms, index terms, system keywords or descriptors.
The benefit of subject headings in our library's databases is that they allow you to easily identify more sources on similar topics, with just a click! See an example:
Do all databases use controlled vocabularies?
While all academic libraries use subject headings in their cataloging (the controlled vocabulary known as the Library of Congress Subject Headings), not all individual databases do. Those that do typically have a subject field listed in the advanced search options. They may also link to their vocabulary list (look for a link to "subjects" or "thesaurus" within the database). See an example from an EBSCO database:
How is a controlled vocabulary term different from a keyword?
Keywords are words and phrases found within the text of the source itself (that is, the author's words) -- and they are also the words you use to search a database or search engine.
You can use subject headings as keywords when you search, of course. Just remember that subject headings will often be broader in nature than your specific topic. For example, there may not be a subject heading for "parkour". Instead, the database might use the more general term "extreme sports."