while loop in Python

What is a while Loop? A while loop in Python is used to execute a block of code repeatedly as long as a specified condition remains True.

It is mainly used when we don’t know in advance how many times you want to execute the loop.

Syntax

while condition:
    # code block

Explanation:

condition: A boolean expression (True or False).
The loop runs while the condition is True.
Once the condition becomes False, the loop stops.

Example: Basic while Loop.

Python

# Initialize variable
count = 1

# Run loop while condition is True
while count <= 5:
    print("Count is:", count)
    count = count + 1  # Increment to avoid infinite loop

Output: Count is: 1
Count is: 2
Count is: 3
Count is: 4
Count is: 5

Explanation

The loop starts with count = 1.
It checks count <= 5 → True.
Prints the value and increases it by 1.
When count becomes 6, the condition becomes False, and the loop stops.

Infinite Loop Example If we forget to update the variable inside the loop, the loop never ends.

Python

# Warning: This will run forever!
x = 1
while x <= 5:
    print("x =", x)
    # missing x = x + 1

So, always ensure the condition will eventually become False.

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