Answered By: Mary Ann Cullen
Last Updated: Aug 03, 2020     Views: 1007

Boolean operators are words used to connect search terms (keywords) to improve your database search results. Most search engines assume you want results containing all of the search terms you enter in the search box, but some research databases require that you use Boolean operators between keywords. Even when not required, searching databases, the GIL library catalogs or even search engines like Google can be more effective if you use Boolean operators appropriately. 

The most commonly used Boolean operators are AND, OR, and NOT.  

AND - search results will contain both search terms 

OR - search results will contain one or both search terms 

NOT - search results will contain the first search term but will not include the term following NOT. 


To learn more about Boolean operators, try this Boolean Operator Video from University of Alabama Libraries. 


For more help, ask a librarian.


updated 6/29/2020 kas