This book not only assists first-time JavaScript programmers, but is an excellent reference for the more experienced developers. The examples are first-rate, and the reference sections are more comprehensive than any I've seen for this language. A MUST if you are a serious JavaScript professional.

I feel that this book is really a work of art. Besides agreeing with the last reviewer that it is not fair to consider this as a book for beginners and then judge it against that standard, I'd say that even though it is not for beginners, it does not make unnecessary arcane references, etc. It is very readable, at least for someone who's had a little experience working with JavaScript. I'd say it is not even a requirement to know object oriented principles (except for those sections perhaps). The author has not only made intelligible so many of the quirks of JavaScript, but provides code which is easy to follow yet extremely useful.

As far as examples, while for JavaScript fans, it might have been nice that the book expanded into 2000 pages instead of almost 1000 that it is now, the author does, I feel, what is necessary to both explain and demonstrate the concepts, and most often, does so by creating VERY useful utility functions and "classes". Just for the utility functions alone, the book would be worth it, really. There are only a very few places where the author suggests to look elsewhere, and besides my not minding doing so given how the book already saved me so much time, the cited references would have taken up unnecessary space if the author were to include them (and they definitely weren't essential).

The book is not outdated! Unlike other books, most of the book is rarely tied down to code that can become outdated as browsers change (like the changeable but helpful quirksmode.org ). Of course, as a big fan of this book, I hope the author will be persuaded to keep making new editions (and make a hardcover!). If you really want to learn the language, this is THE book.

This book was no doubt an immense labor of love--you can feel the author is human, actually teaching, and is not trying to show off with terminology while he still does explain a whole lot of necessary terms, etc., comments the code well, etc. As with art (not the strange modern variety either), I am flabbergasted some people cannot appreciate its beauty. In a complex JavaScript application, I am building, I am using no less than 7 of the utility classes he provided in the book.

For those studying JavaScript in depth / reading this book, I'd recommend one supplement to the book: the informative articles at http://javascript.crockford.com/ (and no doubt that author's book too). The articles on private members and classical vs. prototypal inheritance are one area I felt for which additional examples and use of terminology was helpful, and allowed me to appreciate and understand the chapter in the book on classes more fully (and utilize the approaches in its utility classes as well).

I bought this book after the helpful reviews found on amazon. This book is must have for reference, I've been using this for the past one month and its been great reference for me, a beginner.

This work is great as reference once one has acquired some skill, however it is not a good introduction for starters.

This book is perfect for anyone working on Web sites and uses JavaScript. From learning JavaScript to finding "recipes" on doing work, this book has it all. I cut a project from 10 hours to 1 hour with this book's help.