The terms used by database providers or print index editors to describe a subject.

Each entry references this standardized list of subject headings, often referring users to the correct term.

You can use controlled vocabulary to search a database more effectively.

But understand

• different databases use different terms for the same concept

• some databases or print indexes that have been around for a long time change the terms without going back and revising earlier entries.

The terms used to search for information.

But be aware,

words that need to appear together in the result need to kept together in the search. To do this, a phrase is constructed.

A phrase is a way to search for a series of terms exactly as entered. Most commonly, putting quotation marks " " around the phrase will instruct the search engine or database to look for the phrase as entered, for example: "rock and roll hall of fame" or "Patricia Cornwell". This causes the engine to include all the words, including stopwords.

This is especially helpful when searching for proper names.

Many search tools typically list results in which
the keywords are adjacent and sequential first, which means that you will get different results if you put your search terms in a different order in different searches.

For example:

science fiction

would produce different results than

fiction science

Words that search engines or databases sometimes ignore because they are too common. This is less of a problem than it used to be, because some search engines search them anyway. Nevertheless, it is better to leave them out because using them to search with would reduce the precision of the search.

Sometimes, you may need to include them in your search. Often:

you can use quotation marks " " around the phrase

or

put a + (plus sign) in front of the word to force the tool to include it in the search.