Boolean operators give you control over your searches to find what you need more efficiently.
The three Boolean operators are AND, OR, and NOT. These operators act in different ways to expand or refine your search results when you search for multiple keywords. Here's what they do.
The AND operator narrows your search results by showing you the overlap between keywords. Search results must include both keywords to appear in your results list.
AND is useful when your topic has multiple parts. For example, you might be researching the effect of one thing on another, or you might be studying something in a particular geographic area. Combining your terms using AND can help you get to research about these relationships more quickly.
The OR operator expands your search results by showing you all results that match either keyword. Search results may include either keyword or both keywords. OR is the most expansive Boolean operator.
OR is very useful when your topic can be described in different ways or when your search terms have many variants. Example: women OR girls OR female
The NOT operator narrows your search results by excluding results that match certain keywords. Use NOT when your search term has multiple meanings that are throwing off your results. For example, "migration NOT birds" could be useful if you are studying the migration of people.
Only use NOT once you have tried a search and notice a particular term/concept is throwing off your results. Otherwise, you might exclude useful information without realizing it.
For more about using Boolean operators, watch this brief video.
