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Boolean Logic

When searching online, you can narrow down or broaden your search by using Boolean logic. Use keywords and/or subjects in combination with AND, OR, AND NOT, and "quotation marks" . Effectively using these terms can result in better hits in your results list.

For example, each combination below yields different results.

civil AND war	This search string would narrow down your results. Only sites that include both terms would be found, but the terms do not need to be related each other. For example, you might find sites about civil ceremonies during World War I.
civil OR war	This search would result in many hits. Every site will include either Civil or War. You would get many sites, some useful and some useless! It would be a great deal of work to weed out the good from the bad.
civil AND NOT war	This search would NEVER show any Civil War sites. You would probably get sites about civil law, civil disobedience, civil court, etc.
"civil war"	The use of quotation marks forces the search engine to find both terms, Civil War, together on the site.

Also, remember to read the "Help" section of each search engine for other useful tips