Use these three powerful little words - called Boolean operators - to create better searches.
What are Boolean operators?
Boolean operators are words that we use to link two or more keywords while searching. Linking your keywords with the words AND, OR, and NOT help to expand or narrow the results you get while searching.
AND
- AND tells the catalog or database you are searching in that you are requiring both terms to be in your results. Linking two keywords with the word AND ensures that all of your search results have keyword #1 AND keyword #2.
- Use this Boolean operator when you are comparing, contrasting, or otherwise relating two keywords!
- Example: "peanut butter" AND jelly
- Will only show me results that contain both peanut butter AND jelly
OR
- OR tells the catalog or database you are searching in that you are okay with either keyword (or both keywords) appearing in your search results. Linking two keywords with the word OR ensure that all results with have either keyword #1 OR keyword #2 OR both.
- Use this operator to find information about any of your keywords when you do not need one resource to contain every keyword you search.
- Example: "peanut butter" OR jelly
- Will return results that include peanut butter; jelly; and peanut butter and jelly
NOT
- NOT tells the catalog or database you are searching in that you only want results containing one keyword, but NOT the other. Linking two keywords with the word NOT will only return results containing keyword #1 but NOT keyword #2.
- Use this Boolean operator when you have noticed that searching for keyword #1 also returns results about keyword #2, but that is not what you are looking for.
- Example: "peanut butter" NOT jelly
- Will return results that contain peanut butter, but NOT results that contain jelly.

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