Computer (also known as Web, online, etc.) searching is based on matching the words you enter with the words in the document. To search for these words, connectors, called Boolean Operators, are used. These operators are :
OR - retrieves records that contain either term (electronic mail OR email) notice that these are similar terms. ORs broaden your search to let you retrieve whichever term the "author" used.
AND - retrieves records that contain both terms (pizza AND college). ANDs will be used to connect the major concepts from the search strategy. These operators will narrow the search.
NOT is the operator that excludes records from the search. The search (Music NOT Classical) will retrieve all of the records containing the term Music but will exclude those that contain Classical Music.