Boolean Operators
Boolean Operators are used in keyword searches to link together two or more terms. The most commonly-used operators are: AND and OR.
AND narrows a search; you get fewer records because each concept must be present in the records found — here the area in blue below. Use AND to combine different concepts in one search.
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OR broadens a search; you get more records because OR includes each of the concepts separately, as well as the concepts when found together. OR is often used to link together related concepts.
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Watch the brief video below for a more detailed description of how Boolean Operators are used to connect and define the relationship between your search terms using AND, OR, or NOT.