# Logical Operators in Python

Logical operators are used to perform logical operations of given expressions (relational expressions) or variables.

There are three logical operators available in Python. Letâ€™s discuss one by one.

## Logical or operator

If one of the operands or expressions is true, it will return 1.

If all of them are false, it will return 0.

A B A or B Example
0 0 0 (5 > 10) or (5 < 4)         Both expressions are false. so, logical 'or' output will be 0
0 1 1 (10 > 20) or (10 < 20)    First expression is false and second one is true. so, logical 'or' output will be 1
1 0 1 (10 < 20) or (10 > 100)   First expression is true and second one is false. so, logical 'or' output will be 1
1 1 1 (10 < 20) or (10 < 100)   Both expressions are true. so, logical 'or' output will be 1

## Logical and operator

If both left and right operands or expressions are true, it will return true. Otherwise, it will return false.

Note, non-zero value operands are considered as true.

A B A and B Example
0 0 0 (5 > 10) and (5 < 4)         Both expressions are false. so, logical 'and' output will be 0
0 1 0 (10 > 20) and (10 < 20)    First expression is false and second one is true. so, logical 'and' output will be 0
1 0 0 (10 < 20) and (10 > 100)   First expression is true and second one is false. so, logical 'and' output will be 0
1 1 1 (10 < 20) and (10 < 100)   Both expressions are true. so, logical 'and' output will be 1

## Logical not operator

Logical not operator is used to inverse the current decision. Say, if current state is true, Logical not operator will make it as false.

A not(A) Example
0 1 not(100 < 10)   100 is greater than 10. So, it will return false.
not(false) ==> true
1 0 not(10 < 100)   10 is less than 100. So, it will return true.
not(true) ==> false

## Sample Program

Example

```#python logical operators

a = 5
b = 10

ret = ( (a <= b) or (a != b) )
# 5 <= 10 ==> true. 5 != 10 ==> true. So, true(1) or true(1) will return true.
print("Return value of first expression is ", ret)

ret = ( ( a < b) and (a == b ) )
# 5 < 10 ==>true. 5 == 10 ==> false. So, true(1) and false(0) will return false.
print("Return value of second expression is ", ret)

ret = not ( ( a < b) and (a == b ) )
#   we have used the same expression here.
#   And its result was false.
#   So not(false) will be true.
print("Return value of third expression is ", ret)
```