The document describes how a while loop works in Python. It uses an example of a program that prints numbers from 1 to 4 using a while loop. The while loop initializes a variable x as 1, then checks if x is less than 5, prints x, and increments x by 1 each iteration, repeating until the condition x < 5 is no longer true when x becomes 5.

1. Working of the while loop in Python
Let us see how a while loop in Python works. Consider a program that
displays numbers from 1 to 4.
x = 1
while x<5:
print x
x=x + 1
1
2
3
4
Program Output

2. Code
1
x
x < 9
2 1
True
Working Output
x = 1
while x<5:
print x
x=x + 1

3. Code
2
x
x < 9
3 1
True
Working Output
2
x = 1
while x<5:
print x
x=x + 1

4. Code
3
x
x < 5
4 1
True
Working Output
2
3
x = 1
while x<5:
print x
x=x + 1

5. Code
x = 1
while x<5:
print x
x=x + 1
4
x
x < 5
5 1
True
Working Output
2
3
4

6. Code
x = 1
while x<5:
print x
x=x + 1
5
x
x < 5
1
False
Working Output
2
3
4
Since condition evaluates to False,
thus loop is terminated