In case you’ve been living in a cave, Ajax is the hot new buzzword in web development, made popular by Google applications like gmail and Google Maps, and also by Yahoo Mail. It isn’t really a new technology, but rather an emergent phenomenon in web design, made possible by improving de facto standards compatibility among browsers, better programming and debugging tools, and of course, motivated programmers. In brief, Ajax uses remote callbacks to the originating webserver from a Javascript program in a webpage, allowing for much more responsive interfaces.

This new book by Asleson and Schutta makes the technology easy to understand, revives interest in Javascript programming, and is probably the fastest way to get into writing Ajax-enabled web applications right away.

At under 300 pages in length, this book is pleasantly concise, and it cuts straight to the important parts of the technology. Admittedly, Ajax is not terribly complicated, so this isn’t hard, but the authors have avoided the temptation to pad or overcomplicate the material. It’s well organized, so that after reading it, you’ll likely want to keep it near the computer if you decide to put Ajax to work.

If you want to develop Ajax web applications, you should get this book

The contents

The book starts out with a simple explanation of what AJAX (which originally stood for “Asynchronous Javascript And XML”, but the meaning has drifted a bit) is, as you would expect. This is important, because many people seem to be confused by this. It is not a new language or even a software package—it’s just a technique, which has been possible for some time. The snappy name has definitely helped it to gain popularity, though the real thrust has come from the examples set by Google and Yahoo in deploying responsive web applications.

After that, the book spends three chapters explaining how to use the particular callback mechanisms that define Ajax, then three more chapters on the equally important matter of bringing programmers up to speed on Javascript and the nearly synonymous browser document object model (DOM). Javascript has gone through a slow process of standardization, extension, and improvement, as have the tools used to program it. Extreme programming has become the style of choice for free software developers, and this book explores some of the necessary tools for applying it to Javascript, including a unit test framework. Programmers burned by past experiences with it need to be encouraged to try the water again, and this book makes it clear how to do that in style.

The book concludes with a small example project.

Who’s this book for?

Clearly, this is a book for web programmers. It starts from the assumption that you know the basics of programming, and you really should’ve used Javascript before. But the finer points, especially about the DOM and setting up a good development environment to develop Javascript “like a pro” are explained.

Relevance to free software

Aside from the necessary nods to Internet Explorer (which is generally required because it is both the most commonly used and the least standards compatible browser), this book is entirely about free software. The Mozilla based Javascript development environment consists mostly of tools used by Mozilla developers themselves like Venkman, the Javascript debugging tool.

It’s well organized, so that after reading it, you’ll likely want to keep it near the computer if you decide to put Ajax to work

Pros

The book is concisely and clearly written. If you want to develop Ajax web applications, you should get this book.

Cons

Frankly, the only reasons for not getting this book would be: you invented Ajax, you never in your life want to use it, or you’ve managed to borrow a copy.