Boolean operators

From Computer Science Wiki
Jump to navigation Jump to search
This is a basic concept in computer science

In computer science, the Boolean data type is a data type, having two values (usually denoted true and false), intended to represent the truth values of logic and Boolean algebra. It is named after George Boole, who first defined an algebraic system of logic in the mid 19th century. The Boolean data type is primarily associated with conditional statements, which allow different actions and change control flow depending on whether a programmer-specified Boolean condition evaluates to true or false. It is a special case of a more general logical data type; logic does not always have to be Boolean.[1]

Boolean operators[edit]

This website has an interactive tool to help you understand logic gates

Boolean operator Definition Example
AND The result is TRUE ( 1 ) if both inputs are TRUE ( 1 ).
OR The result is TRUE ( 1 ) if either input is TRUE ( 1 )
NOT Also named an inverter. Inverts the result so TRUE ( 1 ) becomes FALSE ( 0 ) and FALSE ( 0 ) becomes TRUE ( 1 ).
NAND Also named a "Negative AND" The result is TRUE ( 1 ) if both inputs are FALSE ( 0 ).
NOR Also named "Negative OR". The result is TRUE ( 1 ) if any of the inputs are FALSE ( 0 ).
XOR Also named a "Exclusive OR". The result is TRUE ( 1 ) if either input is TRUE ( 1 ) but not if both inputs are TRUE ( 1 ).

This is one of the better videos I've seen on boolean. Content gratefully used with permission : [2]

A helpful android app[edit]

This app is a good tool to practice your boolean logic! Thank you to Max N. for the suggestion!

Truth Tables[edit]

Boolean Logic and Logic Gates[edit]

From crash course computer science comes this EXCELLENT video teaching us about boolean logic and logic gates[3]


  • Define the Boolean operators: AND, OR, NOT, NAND, NOR and XOR.
  • Construct truth tables using the above operators.
  • Construct a logic diagram using AND, OR, NOT, NAND, NOR and XOR gates.


Give the precise meaning of a word, phrase, concept or physical quantity.

Develop information in a diagrammatic or logical form.