Logical Operators

The logical operators act only upon "boolean" variables, namely, true or false.

The logical operator NOT allows users to evaluate conditions that are best expressed in a negative way.  Basically, it reverses the logical value of the condition on which it operates.

Variable        Not(Variable)        

false                true        

true                false        

The And logical operator is a comparison operator between two or more boolean variables.  It returns true if both conditions are true.

Variable A        Variable B        A and B        

false                false                false        

true                true                true        

false                true                false        

true                false                false        

The Or logical operator is a comparison operator between two or more boolean variables.  It returns true if either of the conditions are true.

Variable A        Variable B        A or B        

false                false                false        

true                true                true        

false                true                true        

true                false                true        

The Xor logical operator is a comparison operator between two or more boolean variables.  It returns true only if one of the conditions are true.

Variable A        Variable B        A xor B        

false                false                false        

true                true                false        

false                true                true        

true                false                true