What are Boolean Operators? Mrs. Sereno & Mrs. Gadbury 2012

No… they aren’t leaning ghosts…. Image courtesy of Halloweenclipart.com

Boolean operators are named after George Boole, an Englishman, who invented them as part of a system of logic in the mid-1800's. The most common Boolean operators are AND, OR, NOT and additionally, () can be used In math, they are used to connect logical statements For accessing information, they are used to combine search terms when doing research

And Would everybody wearing Jeans, please stand up # _____ Would everybody wearing tennis shoes please stand up # _____ Would everybody wearing jeans AND tennis shoes please stand up # _____ Image courtesy of zimbio.com Image courtesy of +

Venn Diagram of AND War Photography

AND Explained limit Using the operator AND between keywords will limit the results of a search because all 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 tennis shoes please stand up #______ Would everybody wearing jeans OR tennis shoes please stand up#______ Image courtesy of zimbio.com Image courtesy of OR

Venn Diagram of OR War Photography

OR Explained eitherboth 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 tennis shoes, please stand up Image courtesy of zimbio.com Image courtesy of

Venn Diagram for NOT Photography War

( ) Used to group together words or phrases, for example (domestic AND violence) AND (court OR trial) could be used to search for cases of domestic violence that have been gone to court or trial

Order of operators Just as in math, certain operators are done first. The order for Boolean operators is: ( ) NOT AND OR

Be sure to use proper search structure What would the following search bring up? Dogs AND ((rabies OR rabid) NOT (domestic OR Pet) ) The search will look for the words rabies or rabid Then domestic or pet Then remove all results that contain the words domestic or pet from the results Then remove anything that does not contain the word dog from the results Image courtesy of mediworldrkr.blogspot.com

Now let’s try one on our own in the WUHS SHARE catalog I am looking to see if there is any information about ocean mammals in Alaska, like dolphins and porpoises, but I don’t need any more information about whales. What is the best Boolean phrase to build for this search? (answer on following slide!)

Alaska AND (dolphins or porpoises) NOT whales