Functions Basics

Functions are the building blocks of reusable code. They group logic together so we can call it whenever needed, preventing code duplication. A function only runs when it is called.

Defining and Calling​

Use the def keyword to define a function. Indentation is critical in Python to define the function body. Variables in the definition are called parameters, while the values we pass in are called arguments.

def greet_user(name):
    """Simple greeting function."""
    print(f"Hello, {name}!")

# Calling the function
greet_user("Alice")

Output:

Hello, Alice!