What is Loops in Python?

In Python, loops are used to execute a block of code repeatedly as long as a condition is true. There are two primary types of loops in Python:

1. for loop:

The for loop iterates over a sequence (such as a list, tuple, string, or range) and executes a block of code for each item in the sequence.

Syntax:

for variable in sequence:
    # code block

Example:

for i in range(5):
    print(i)

This will print:

0
1
2
3
4

In this case, the for loop iterates over the numbers from 0 to 4 (generated by range(5)) and prints each number.

2. while loop:

The while loop executes a block of code as long as a specified condition is true. It keeps checking the condition before each iteration.

Syntax:

while condition:
    # code block

Example:

i = 0
while i < 5:
    print(i)
    i += 1

This will also print:

0
1
2
3
4

In this example, the loop continues to run as long as the condition i < 5 remains true. The variable i is incremented by 1 each time to avoid an infinite loop.

Key Concepts:

• break: Exits the loop prematurely.
• continue: Skips the current iteration and moves to the next iteration.
• else: The else block is optional and will execute when the loop completes normally (without hitting a break).

Example with else and break:

for i in range(5):
    if i == 3:
        break
    print(i)
else:
    print("Loop completed")  # This won't be printed because the loop was broken

Output:

0
1
2

Loops are essential for repetitive tasks in Python and are a core part of the language’s control flow.