Preface

Welcome to the 2nd edition of the widely acclaimed You Don’t Know JS (YDKJS) book series: You Don’t Know JS Yet (YDKJSY).

If you’ve read any of the 1st edition books, you can expect a refreshed approach in these new ones, with plenty of updated coverage of what’s changed in JS over the last five years. But what I hope and believe you’ll still get is the same commitment to respecting JS and digging into what really makes it tick.

If this is your first time reading these books, I’m glad you’re here. Prepare for a deep and extensive journey into all the corners of JavaScript.

If you are new to programming or JS, be aware that these books are not intended as a gentle “intro to JavaScript.” This material is, at times, complex and challenging, and goes much deeper than is typical for a first-time learner. You’re welcome here no matter what your background is, but these books are written assuming you’re already comfortable with JS and have at least 6–9 months experience with it.