Locating and Using Subject Headings

A subject heading is a word or phrase that describes the content of a resource or item. For example, the word "cookery" is often assigned in databases to records or items that are about cooking. As "cookery" can describe many forms and types of cooking, additional words may be assigned to further describe the resource or item.

• Cookery, French
• Cookery, Mexican
• Cookery -- medical diets

"Cooking" is also a subject term:

• Cooking (Venison)
• Cooking (Fish)

Subject headings are usually pre-assigned. The decision to assign a word or phrase to a particular content is why subject headings are sometimes called "controlled vocabulary." The UC Merced Library uses US Library of Congress Subject Headings (LCSH). The LCSH system of classification is the most commonly used subject heading system in college and university libraries in the United States.

Like subject headings, keywords, or key words, are words or phrases that describe the content of a resource or item record in a database. They can be words that are included in the title of a book, journal title, film, or other resource. Unlike subject headings, they are not part of any list of officiallly assigned words, or controlled vocabulary.

For example, the official subject heading in the LCSH for matters relating to cooking is "cookery." But most people looking for resources on how to prepare food will look for "cooking," not "cookery." Searching for the keyword "cooking" won't retrieve items on cookery unless that specific word "cooking" is found somewhere in the item's database record.

A drawback of using keywords instead of subject terms when searching databases is that sometimes your search will produce records for items that are unrelated to your search. You may use "cooking" to find cookbooks, but that keyword will find both of the following titles:

Cooking for grillmasters: Everything you need to know about outdoor grilling

AND

Cooking the books: Fraud in corporate accounting

Depending on what you need, both subject headings and keywords are valid ways to search databases for resources.