You Don't Know JS Yet
The 2nd-edition rewrite of Kyle Simpson's deep dive into JavaScript: scope and closures, the `this` binding rules, type coercion semantics, sync/async patterns, and the language's modern features. CC BY-NC-ND 4.0 — exercises lift Simpson's example code (MIT) and let learners drill the load-bearing primitives.
- JavaScript
- 25 lessons
- ~5 hours
- Free
- by Kyle Simpson
Learn JavaScript for free on Libre Academy with the You Don't Know JS Yet course: 25 interactive lessons you complete by writing real code in a built-in editor, graded instantly by hidden tests. No paywall, no sign-up. It's part of the free, open-source desktop app for macOS, Windows and Linux.
What you get
- Hands-on lessons with a real editor and instant, test-graded feedback.
- Free and open source, with no account required to start.
- Works offline in the free desktop app for macOS, Windows and Linux.
- JavaScript runs instantly in the app.
What's inside
- Getting Started
- Scope & Closures
- Objects & Prototypes
- Types & Grammar
- Sync & Async
- ES.Next & Beyond
Download to start You Don't Know JS Yet → More free JavaScript courses
Helpful reading
Why passive video doesn't make you a programmer · Bring Your Own Book: turning any PDF into a course