Boolean operators form the basis of mathematical sets and database logic. They help determine HOW your terms are searched and connect your seach words together to either narrow or broaden your set of results. While there are a number of boolean operators, the two most commonly used are: AND & OR.
Use AND in a search to:
Use OR in a search to:
All three circles represent the result set for this search. It is a big set because any of those words are valid using the OR operator.