Links to More Information about Internet Searching Boolean logic is the means by which search terms can be combined .
Search engines vary as to which operators they accept.
The most common terms are AND , OR and AND NOT . Most of these engines still use explicit Boolean search logic. Thus some familiarity with the Boolean operators remains essential for Internet research. Usually only a few minutes are needed with a search engine's help file to understand how Boolean terms are used in that engine's search operations. If you don't know what your search engine requires, use all capitals.