JavaScript: Functions & Data
Functions are values: pass them around, return them, and capture state. Hands-on lessons where you write every line yourself and every step has to run.
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10 lessons a month on the free tier.
Classes in this course
Functions & closures
Higher-order functions and the closures that give them memory.
Also coming to this course
Async JavaScript
How CodeTrain teaches this
No videos and no multiple-choice quiz at the end. Each lesson is a handful of small steps in a real editor. You type the code yourself, it runs, and the tutor reviews what you actually wrote. It will not hand you the answer, and the step doesn't advance until your code passes. What you get at the end is a record of which steps you wrote unaided, not a completion percentage.