Boolean operators are words (or, and, not) used to connect search terms to expand or narrow a search within a database to locate relevant information.
It is helpful to diagram the effects of these operators:
women or females |
Or retrieves records that contain anyof the search terms. It expands the search. Therefore, use "or" in between terms that have the same meaning (synonyms) or equal value to the search. |
women and media |
And retrieves records that contain all of the search terms. It narrows or limits the search. Therefore, use "and" in between terms that are required to make the search specific. |
image not weight |
Not eliminates records that contain a search term. It narrows or limits the search. Therefore, use "not" in front of a term to ensure that the search will not include that term. Warning: Some databases use "and not" instead of "not." Check the database help screen. |
Variety of terms: If you are looking for items on the "movies," use additional keywords such as "film," "films," "cinema," or "motion pictures."
An example of retrieving results unrelated to your topic (false drops): using the keyword "cricket" will retrieve items about the sport as well as the insect.
bank* will retrieve: bank or banks or banking or banker or bankruptcy, etc.
cat* will also retrieve cataclysm, catacomb, catalepsy, catalog, etc.
It's best to use the boolean operator "or" in these instances (cat or cats).
Some databases allow for wild cards to be embedded within a word to replace a single character. For instance, you can also use the question mark (?) within a word to replace a character. For example:
wom?n will retrieve woman or women