What is Boolean Logic?

A type of mathematical logic named after its designer George Boole. This binary algebraic system is used primarily in switching circuits and database searches. Search engines use logical operators called, Boolean Operators (AND, OR, NOT).

AND: Narrows a keyword search by collecting all terms present in the same document.
NOT: Prevents retrieval of unwanted documents containing a keyword.
OR: which broadens a keyword search by linking related terms.