Author: Zachary Kessin
Publisher: O'Reilly, 2011
Pages: 142
ISBN: 978-1449399085
Aimed at: Advanced JavaScript programmers
Rating: 3
Pros: Concise introduction to HTML5 technologies
Cons: Difficult examples with little explanation
Reviewed by: Ian Elliot

This is a very slim book focused on building HTML5 applications. This is  big topic, so can so few pages get you anywhere?

The subtitle of this book is: Building Powerful Cross-Platform Environments in JavaScript and this book really does focus in on JavaScript from the start.

After a short, and dispensable, chapter on the history of the web and how JavaScript became the dominant language, Chapter 2 really gets the book going with "The Power of JavaScript". This is a lightning introduction to advanced JavaScript. While the author clearly understands and admires the language, the very advanced examples are presented without any real explanation. Unless you too are a JavaScript expert you can expect to stare at some of the example for a long while before you understand what they do. Indeed there is even a problem with working out what some of the examples are supposed to do.

In addition to all of this there are lots of small errors which are going to make some readers wonder what point is being made. This is not a good introduction to advanced JavaScript.

Chapter 3 launches into testing using QUnit and Selenium; while this is an interesting topic it probably isn't what the typical reader expects as an early part of an introduction to HTML5 apps.

The core topic really only gets going in Chapter 4 with a look at local storage. Most HTML5 books get to this point much sooner by assuming that you know JavaScript and by putting off general topics such as unit testing until later.

From this point the book moves through the usual HTML5 programming topics in a reasonably logical order - Indexdb, files, working offline, web workers and web sockets. The final chapter is on the new tags introduced in HTML5, which is where most books about it start

Each of the topics is covered well enough and there is some attempt to motivate the ideas by appealing to what you might need to do to create an HTML5 app, but you don't get the feel of an integrated whole. The book does attempt to present HTML5 technologies as a programmer might conceive of them, but it doesn't really dig deep enough. It also doesn't address the problem of browser compatibility and when and where you can expect to make use of the new features.

Overall this book might make a concise introduction to the standard HTML5 technologies, but if you aren't already a good JavaScript programmer you might find it tough going. You can tell that there is a good book trying to get out, but it just doesn't treat the topics in enough depth. At best it is a quick orientation course on HTML5 technologies suitable for the skilled programmer who wants to get up to speed.