BOOLEAN OPERATORS
Whether you know it or not, you have used Boolean operators whenever you have searched in a library catalog or database or used an internet search engine, such as Google.
Searching for single words is a keyword search and searching for multiple words grouped together is a phrase search. Phrase searching is particularly useful when your keywords are frequently used separately but you only want search results that use them together:
If you have a complex research query, you might need to use nesting, which combines sets of Boolean searches using parentheses.
RFID AND (pharmaceuticals OR drugs OR pills) AND "health care"
Sometimes you want to expand your search because of variations in word usage and spelling. If your search contains words that have variations, you can use a truncation: process*
The results from this search would include the desired search term “processor,” as well as additional variants, including “processing, processed, process, processes, processors,” etc. Additionally, the search would include possibly unrelated or undesired results, such as “procession, processional, processionally, processioner,” etc.
Unfortunately, not all catalogs, databases, and search engines use the same characters for wildcards and truncations. So, look for the help option in the resource you are using to find out which characters (?, *, $, %, etc.) should be used.