Function
Domain: Programming Fundamentals
🎯 Motivation
When you do the same thing multiple times, wrapping it in a function avoids repetition and makes code readable.
📋 Concrete Example
def greet(name): return 'Hello, ' + name. Call it: greet('Alice') returns ‘Hello, Alice’.
🔗 Analogy
A recipe card - you write the steps once, then whenever you want that dish, you just follow the card. You can give it different ingredients (arguments) each time.