For Loops

Sometimes we want Python to do the same action again and again.

For example:

• Print a message many times
• Show each letter in a word
• Repeat a task without writing the same code again

A for loop helps us do that.

What Is a Loop?

A loop is code that repeats.

Instead of writing the same line many times, we write it once and let Python repeat it.

What Is a For Loop?

A for loop repeats code one step at a time.

It takes one item, uses it, then moves to the next item.

for letter in "cat":
    print(letter)

How This Example Works

The word "cat" has three letters.

Python works like this:

• First letter is c
• Then letter is a
• Then letter is t
• After the last letter, the loop stops

Output

c
a
t

Another Example

for letter in "dog":
    print(letter)

Using a Variable Name

The word after for is a variable name.

It stores the current item during each repeat.

for character in "hi":
    print(character)

You can choose names like:

• letter
• character
• item

Repeating a Message

A loop can also repeat another action.

for letter in "abc":
    print("Welcome")

Because "abc" has three letters, Welcome prints three times.

Why Indentation Matters

The indented line is the code that repeats.

for letter in "go":
    print(letter)

If the line is not indented, Python will show an error.

Code Along

name = "Sam"

for letter in name:
    print(letter)

Mini Challenge

Build a name printer.

Steps:

• Store your name in a variable
• Use a for loop
• Print each letter on a new line

Real World Use Case

Programs use loops to read text, show products, send messages, and repeat tasks automatically.

Quiz

1. What is a loop?
2. What does a for loop do?
3. What happens after the last item?
4. Why is indentation important?

Assignment

Create a program that stores the word Python and prints each letter on a new line using a for loop.

Summary

You learned that a loop repeats code, and a for loop helps Python go through items one by one.