Boolean searching involves the combination of your search terms with "operators" such as AND, OR, NOT. When you combine search terms with the AND operator, you will retrieve only those Web pages that include both of your terms. When you combine search terms with the OR operator, you will retrieve Web pages that have either one or the other term, but not necessary both terms. Using the NOT operator, you will exclude Web page with that term.See diagram.
Many search engines use a plus (+) or minus (-) sign instead of, or in addition to, Boolean operators. When a plus sign is placed in front of your search term, only Web pages with your term will be retrieved. When a minus sign is placed in front of your search term, Web pages with that term will be removed from your search results.
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