
You Don't Know JS
by Kyle Simpson · first published 2014
123mentions
88recommended by
108HN commenters
2014–2025first – last mentioned
81% recommend15% neutral5% critical
Why HN recommends it
Free, in-depth series on how JavaScript works under the hood: this, object prototypes, scope and ES6. Suits developers with some experience who want to go beyond basics, after an intro like Eloquent JavaScript.
Summarised by Claude from recommending comments
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…purchased it when I first saw it announced by the author and it is, Functional Light JavaScript by Kyle Simpson [4]. Great author that always takes a r ally great approach to explaining things he wrote the You Don’t Know JS series that he released through O’Reilly and also put up on github. Kyle Simpson also has a course on Frontend Masters modeled after his book Functional Light JavaScript. [1]: https://github.com/MostlyAdequate/mostly-adequate-guide/blob...…
on “Ask HN: Resources to Learn Functional Programming?” ↗…downsides to that, the most important being losing out on a lot of changes the language is going through. A video course sounds like a much better option. Anyway, I would recommend the entire series of You don't know JS by Kyle Simpson. I would recommend the video courses by him as well. You can find them on frontendmasters.com
on “Ask HN: How do I learn JavaScript after using it for years” ↗Kyle Simpson and the "You Don't Know JS" series. Can't speak highly enough about them. Also he has a good recent book on Functional Programming, which if you plan on tackling Redux later will be helpful. I got the physical editions because…
on “Ask HN: Resources for learning advanced JavaScript and React” ↗I think JavaScript: The Good Parts is still relevant, you'll just want to supplement it with other resources on ES6, async, etc. I recommend Kyle Simpson's series You Don't Know JS for understanding in depth. Eloquent JavaScript by Marijn Haverbeke is a great interactive resource covering the basics: https://eloquentjavascript.net. For more practical guidance on specific topics…
on “Ask HN: A modern day alternative to “JavaScript the good parts”?” ↗Without doubt Kyle Simpson’s You Don’t Know JS. I am going to say not only is this the best book on any programming language, but that it completely changed my understanding of what a teacher and a good intellectual is.
on “Ask HN: A modern day alternative to “JavaScript the good parts”?” ↗Just popping in to recommend Kyle Simpson’s “You Don’t Know JS” series. He breaks down “this” and other potentially confusing JS concepts in an easy-to-understand way. https://github.com/getify/You-Dont-Know-JS/blob/master/READM...
on “Removing JavaScript's 'this' keyword makes it a better language” ↗Check out Kyle Simpson's "You don't know JS" if you really want a clear understanding on "this" and how it relates to objects in Javascript. https://github.com/getify/You-Dont-Know-JS/tree/master/this%...
on ““This” in JavaScript” ↗…are few best practices, and the ones we have aren't explicitly stated in one universally agreed upon place. My advice to you is this: 1. Focus on learning Javascript firs and foremost. Kyle Simpson's "You Don't Know JS" series is amazing: https://github.com/getify/You-Dont-Know-JS 2. Best practices are hard to come by, they essentially are: Crockford's Javascript The Good Parts, The Mozilla JS docs, and some styleguides…
on “Brunch: Replace gulp, grunt and increase your dev speed” ↗You Don't Know JS by Kyle Simpson is essential if you want to learn Javascript in depth.
on “Ask HN: What are the latest and greatest books on your favorite language?” ↗Im a huge fan of 'You Don't Know JS' by Kyle Simpson (getify) https://github.com/getify/You-Dont-Know-JS
on “Ask HN: What's the best path to learn JavaScript as a beginner?” ↗I think it depends on your learning style & what you want to learn. http://jsbooks.revolunet.com/ is a great resource for free books. If you want to learn concepts, You Don't Know JS by Kyle Simpson is great. If you want to learn by doing, I would look away from books & more towards video based learning. It seems to have richer content in this style. Pluralsight, Frontend Masters,…
on “Ask HN: Best current book to learn JavaScript?” ↗…spending money on a physical copy to thumb through, but it may be a little too slow to get going for someone who already has experience with other languages. For developers, I'd recommend Kyle Simpson's "You Don't Know JS" books, in particular "This & Object Prototypes", followed by "Scopes & Closures". Well written, with plenty of example code, these are deep dives into specific areas which make Javascript different/weird.…
on “Ask HN: Best current book to learn JavaScript?” ↗I found the You Don't Know JS series books by Kyle Simpson very helpful. The last one is for ES6. https://github.com/getify/You-Dont-Know-JS
on “ECMAScript 2017 Language Specification” ↗…https://developer.mozilla.org/en-US/docs/Web/JavaScript - Dr. Axel Rauschmayer's books are the best "full reference" books for all of JS syntax and behavior: http://exploringjs.com/ - Kyle Simpson's "You Don't Know JS" is a deep dive into the way the JS language works: https://github.com/getify/You-Dont-Know-JS I also have links to some additional meta-resources as part of my React/Redux links list: https://github.com/markerikson/react-redux-links/blob/master...…
on “What's the best book to read about JavaScript?” ↗…Pluralsight and Egghead (though Pluralsight also has some introductory and rapid training courses focused on Javascript). The best book for learning how JS works under the surface is Simpson's series 'You Don't Know JS'.
on “Ask HN: Best resources for learning JavaScript in 2017” ↗