What is a Loop in Python?

A loop in Python is used to execute a block of code repeatedly. Instead of writing the same code multiple times, we can use a loop to perform the same task efficiently.

For example, if you want to print “Hello Python” five times, you can use a loop instead of writing five separate print statements.

Python mainly provides two types of loops:

1. for Loop

2. while Loop

In this tutorial, we will learn the Python for loop with simple examples.

1. Python for Loop Syntax

The basic syntax of a for loop is:

for variable in sequence:
    # Code to execute

Explanation:

• for starts the loop.

• variable stores the current item during each iteration.

• in takes items from a sequence.

• sequence can be a list, string, range, or another iterable.

• The indented code runs for each item.

2. Example: Print Numbers from 1 to 5

Python Code:

for i in range(1, 6):
    print(i)

Output:

1
2
3
4
5

Explanation

• range(1, 6) generates numbers from 1 to 5.

• The ending number 6 is not included.

• i receives one number at a time.

• print(i) displays each number.

3. Example: Print a Message 5 Times

for i in range(5):
    print("Hello Python")

Output:

Hello Python
Hello Python
Hello Python
Hello Python
Hello Python

Here, range(5) generates five values: 0, 1, 2, 3, and 4. Therefore, the message prints five times.

4. Example: Calculate the Sum of Numbers from 1 to 10

total = 0

for i in range(1, 11):
    total = total + i

print("Total =", total)

Output:

Total = 55

Explanation

• total = 0 initializes the total.

• The loop generates numbers from 1 to 10.

• total = total + i adds each number to the previous total.

• print() displays the final sum.

For example, the calculation is:

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55

5. Example: Print Items from a List

fruits = ["Apple", "Banana", "Mango"]

for fruit in fruits:
    print(fruit)

Output:

Apple
Banana
Mango

In this example, the loop takes each fruit from the list and prints it one by one.

6. Difference Between for Loop and while Loop

Both loops are useful for automating repetitive tasks in Python.

7. Python Loop Practice Questions

Try solving these questions yourself.

Question 1: Write a Python program to print numbers from 1 to 20.

Question 2: Write a program to print the multiplication table of 5.

Question 3: Write a program to calculate the sum of numbers from 1 to 100.

Question 4: Given the list below, print each student’s name using a for loop.

students = ["Amit", "Rohit", "Priya", "Neha"]

Question 5: Write a program to print all even numbers from 2 to 20.

Conclusion

Python loops are essential for programming and automation. They help reduce repetitive code and make programs easier to maintain. Learning for and while loops will help you build practical Python projects and solve real-world problems.

Keep Practicing!