Boolean Operators Objective: Students will understand Boolean operators and how they function when searching for information.

Boolean logic Boolean logic is named for mathematician George Boole who defined the system of logical operations. Boolean operators are often used when searching article databases, library catalogs, and search engines. The operators show a relationship between keywords in a search. Image taken from a.com/topic/George_Bo ole.aspx

The three Boolean operators are: AND OR NOT Boolean operators are used to expand or limit the number of results in a search.

Diagrams visually explain how Boolean operators work. Use Boolean operators to connect and search for the keywords found in your research question.

For example, SIRS Knowledge Source uses them to perform advanced searches.

Google’s Advanced Search also uses Boolean operators.

AND narrows your search. Use AND when you want your results to include all terms. Only records with both terms will be found (the purple area).

OR broadens your search. Use OR when searching synonyms and closely related keywords. OR will find results with one term or the other or both (the entire green area). ACT SAT

NOT narrows your search. Use NOT when you want to exclude a keyword from your search. Cheating NOT Test will find results with the word Cheating, but will exclude any results with the word Test. TestCheating Only records with the word cheating that do not include the word test will be found (the green area).

You can also combine Boolean operators For example: Cheating AND (ACT OR SAT) This search would find results containing either ACT or SAT or both words (the red & purple areas) AND those areas that overlap with cheating (the purple area). So this search expands your search to include both tests and then limits the results to include just those articles that contain the word cheating. SAT Cheating ACT

Boolean operators are an effective tool when searching article databases, library catalogs, and search engines. AND narrows your search OR broadens your search NOT narrows your search Summing Up