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From your first “Hello, world” to your next big project.
Free lessons, hands-on challenges, and a place to
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A great place to start.
Pick a language. We'll guide you from the very first line.
Big goals. A step-by-step plan.
You don't have to figure it all out. Follow a path that fits your goals.
Python Developer
From your first print statement to your first API.
Full Stack Developer
Connect the dots from a web page to a complete app.
Data Science
Turn curiosity and data into useful discoveries.
Small problems. Real progress.
Reverse a String
Return a new string with its characters in reverse order. Preserve spaces, punctuation, and letter case.
Give it a trySum of an Array
Return the sum of all numbers in the input array. An empty array should return zero.
Give it a tryCount the Vowels
Return the number of vowels (a, e, i, o, u) in the input text. Count uppercase and lowercase vowels.
Give it a tryLearn by building.
Real projects, small steps, and that “I made this” feeling.
Everyday Calculator
Build a calculator that feels as good as it works.
Build this projectA Little To-do List
Make room for the things you want to get done.
Build this projectGuess the Number
A tiny game with a surprising amount to teach you.
Build this project