Boolean operators

Boolean operators or logical operators are the most common form of advanced search, and are used in all databases and the Internet. They allow you to tailor your search to target very specific items or subjects.

There are three operators you can use: "and", "or" and "not". 

• "And" searches for records containing both search words or terms. For example, the search "poverty and crime" will search for records where both the words "poverty" and "crime" occur.
  
  
• "Or" searches for records containing either or both words. For example, the search "college" or "university" will search for records containing either the word "college" or "university", or both words "college and university" in the same record.
  
  
• "Not" searches exclude records that contain a certain term. For example, the search "cats not dogs" will search for records with the word "cats" but will exclude the ones that contain the word "dogs".