Research Help

Boolean Logic consists of three main logical operators or connectors: AND, OR, and NOT

Boolean Operator AND

• Finds sources containing two or more ideas
• The database will only retrieve items containing both words/terms
• AND narrows your search
• You can use AND many times in one search
• Example: books AND censorship
• Example: Jesus AND miracles

Boolean Operator OR

• Use OR when searching for synonyms
• OR tells the database that the words can be used interchangeably, so it will retrieve items containing either word
• Or broadens your search to include synonyms anmd related words or even unrelated words
• You can use OR many times in one search
• Example: books OR films
• Example: Jesus OR Messiah

Boolean Operator NOT

• Use NOT when you wish to exclude records from your search results
• Be careful when using NOT. The term you want may be present in an important way in results that also contain the word you wish to avoid.
• Example: books NOT politics
• Example: trump NOT president [if you are researching the idea of one idea outweighing (or "trumping") another idea, but do not wish to receive results about President Donald Trump]

Combining Operators

• Make complex searches using more than one Boolean operator at a time
• Make complex search terms by putting parentheses around synonyms
• The NOT operator has to go at the end of your search string
• Example: (electronic OR internet OR web) AND (vote OR voting)
• Example: (Jesus OR Messiah OR Christ) AND (miracles OR supernatural OR healing)

Most of this information was created by the librarians at East Texas Baptist University. Check out their LibGuides here.

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