Functions: Reusable Code Blocks 🧩

A function is a reusable block of code that performs a specific task.

Defining a Function

def greet():
    print("Hello!")

# Call the function
greet()  # Output: Hello!

Why Use Functions?

1. Reusability: Write once, use many times
2. Organization: Break complex programs into smaller pieces
3. Readability: Give meaningful names to operations
4. Testing: Easier to test individual parts

Function Anatomy

def function_name():
    # Code block (indented)
    # This runs when function is called
    pass

Key Points:

• Start with

  def

  keyword
• Give it a descriptive name
• Don't forget the colon

  :

• Indent the body (4 spaces)