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Operators, which are also called connectors,
are used in conjunction with search terms to broaden (expand)
and narrow (restrict) searches to increase the number of relevant
Since most searches involve more than one word, a means of combining
terms, searching for synonyms, and eliminating terms is useful. Boolean
operators allow these processes in online search tools such as library
databases and Internet search engines. The three most commonly used
boolean operators are explained below.
TO CREATE BOOLEAN SEARCHES
Explaining how to use boolean operators works best when using examples.
Therefore, the following examples show how to use the boolean operators
"and," "or," and "not." The examples
incorporate search terms that might be used to locate information
about how small groups make decisions. The purple-shaded areas indicate
the amount of material that would be returned using each operator.
operators can be combined in many ways and used separately or together.
Often these combinations are more effective when also using a technique
called "nesting," which is discussed on a separate page
in this unit.