Boolean Operators Boolean operators are named after George
Boolean Operators
¢ Boolean operators are named after George Boole, an Englishman, who invented them as part of a system of logic in the mid-1800's. l The most common Boolean operators are AND, OR, NOT and NEAR, additionally, () and “ ”can be used. l They are used to combine search terms when doing research.
And ¢ Would everybody wearing Jeans, please stand up # _____ ¢ Would everybody wearing Sneakers please stand up # _____ ¢ Would everybody wearing jeans and sneakers please stand up # _____
Venn Diagram of AND Jeans Sneakers
AND Explained ¢ Using the operator AND between keywords will limit the results of a search because all of the keywords have to be present in order for an item to be retrieved.
OR ¢ Would everybody wearing jeans please stand up #______ ¢ Would everybody wearing sneakers please stand up #______ ¢ Would everybody wearing jeans OR sneakers please stand up #______
Venn Diagram of OR Jeans Sneakers
OR Explained Using the OR operator results in either or both of your search terms appearing in your results. ¢ Using the OR operator will result in a larger number of retrieved items and therefore expands the search. ¢
NOT ¢ The NOT (or AND NOT) operator forbids the word after it from appearing in the items resulting from your search. ¢ Would everybody wearing Jeans but NOT sneakers, please stand up
Venn Diagram for NOT Jeans Sneakers
NOT Explained Not helps to limit your search because it takes out a category of undesirable results. ¢ NOT or AND NOT thus narrows or limits a search by excluding the keyword immediately following it. ¢
NEAR Finds the terms within 10 words of each other ¢ Domestic NEAR Violence ¢ l would make sure these two words appeared close enough to each other that they would be referring to domestic violence
( ) or “ ” ¢ Used to group together words or phrases, for example (domestic NEAR violence) and (police AND trial) “domestic violence” “police trial”
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