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Boolean Logic: Boolean Logic

PowerPoint presentation describing the use of Boolean Logic in Online Searching

Boolean Logic PowerPoint Presentation

Select the link below to discover what is Boolean Logic and how it will make your online searching more efficient and more effective.

What it is

Boolean Logic is Algebra that works with logical rather than numeric relationships.

  • Boolean algebra was introduced in 1854 by George Boole
  • Boole devised a mathematical language to deal with questions of logic.
  • Boole is now considered the father of modern information technology

Algebra comes from the Arabic al-jebr meaning "reunion of broken parts" (jebr can be pronounced either gobre or jobre)

  • Algebra uses letter to represent unknown number
  • In Algebra variables like x and y = numerical values
    • for example x + 4 = 8

Boolean Logic is a form of algebra in which the variables have a logical value of TRUE or FALSE.

  • In Boolean algebra x and y = classes of objects
    • for example x = triangles and y = circles   

Boolean Operators

AND = Can be thought of as BOTH.  It requires that both or all objects (search terms) be present in the results.  In online searching AND serves to narrow the search and is used for combining differing concepts.

OR = Can be thought of as EITHER.  It is used to find either one term or another.  In online searching OR serves to broaden a search and is used to search synonymous or closely related terms.

NOT = Can be thought of as AND NOT.  It is used to eliminate records.  In online searching it serves to narrow a search.  Exercise caution when using the Boolean NOT as needed concepts may be eliminated unintentionally.

Boolean Video

Boolean Operators defined

Boolean Operators

Boolean Operators with Set Theory & Venn Diagram


Venn Diagram

Boolean Logic

Set Theory

Boolean Logic

Reference Librarian

Janet Tillman, "Miss T."'s picture
Janet Tillman, "Miss T."
The Master's University
21726 Placerita Canyon. Rd.
Santa Clarita, CA 91321