Boolean Research Efficiency

Most online databases and search engines support Boolean searches. Boolean search techniques can be used to carry out effective searches, cutting out many unrelated documents.

When a basic search (a one word or phrase search) fails to deliver the precise search results needed, researchers can key in a "Search String" using boolean operators to narrow or broaden a search. 

Boolean operators connect your search words together to either narrow or broaden your set of results.

The four basic boolean operators are: AND, OR, NOT and " ".

Why use Boolean operators?

        To focus a search, particularly when your topic contains 

        multiple search terms.

AND

Use AND in a search string to narrow your results and tell the database that ALL search terms must be present in the search results.

Using AND will retrieve documents that use both the search terms you specify.

                Example: myths AND Egyptian

OR

Use OR in a search string to connect two or more similar concepts  and to broaden your results, telling the database that ANY of your search terms can be present in the search results.

OR is a good tool to use when there are several common spellings or synonyms of a word, for example color OR colour.

                 Example: myths or legends

NOT

Use NOT in a search string to exclude words from your search and narrow your search, telling the database to ignore concepts that may be implied by your search terms.

Using NOT retrieves documents that contain one, but not the other, of the search terms you enter.

                 Example: myths NOT Egyptian

" "

Surround a search term with " " when your search term consists of two or more words that you want to be searched as a unit instead of separately.

                 Example: "Egyptian mythology"