Functions

Name it once, use it everywhere

An interactive lesson with 7 steps, about 6 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• A function is a named, reusable piece of code; def defines it, calling runs it.
• Arguments fill the function’s variables; return hands back a value.
• Functions avoid repetition; recursive functions call themselves on smaller cases.

Steps

1. Making your own instructions
2. Watching a call
3. A function of a function
4. A flower from squares
5. Why bother?
6. A function that calls itself
7. A recursive sum