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Thesis Scrutiny, Thesis Consultation & Information Literacy Sessions @ Mona Information Literacy Unit (MILU): Boolean Operators

What to look for

Boolean operators form the basis of mathematics sets and database logic. 

  • They connect your search words together to either narrow or broaden your set of results.
  • The three basic Boolean Operators are AND, OR, and NOT.

Why use Boolean Operators?

  • To focus a search, particularly when your topic contains multiple search terms.
  • To connect various pieces of information to find exactly what you're looking for.
  • Example: second creation (title) AND Wilmut and Campbell (author) AND 2000 (year).

Search Order

Databases follow commands you type in and return results based on those commands. Be aware of the logical order in which words are connected using Boolean Operators.

  • Databases usually recognize AND as the remarry operator and will connect concepts with AND together first.
  • If you use a combination of AND and OR operators in a search, enclose the words to be "ORed" together in parentheses .


  • Ethics AND (closing OR reproductive techniques)
  • (ethic* OR moral*) AND ( bioengineering OR Cloning) 

Tutorials on Boolean Operators

Introduction to UWIlinC

UWIlinC brings together UWI information resources from across the English-speaking Caribbean in all formats including UWI's intellectual output, subscribed resources (electronic journals, databases, electronic books) and the catalogues for all four UWI campuses.