What is AJAX?

A new technique?

Wikipedia defines the term AJAX as Asynchronous JavaScript And XML, I actually think Asynchronous JavaScript Across XML is slightly sexier but really it is just a buzzword for tools are a technique that can be used to better the web experience. Lets take a detailed look at the terms Ajax defines.

Asynchronous - This is probably the most powerful implication of the AJAX model. That is to say AJAX enables the client to thread out multiple processes and requests for parallel processing of data, thereby upping your efficiency of your application.

JavaScript - Hopefully if your here you understand that JavaScript to be the established standards compliant language of the web.

Across XML - The last piece of the puzzle is really a data storage format. The web is basically a flat place and XML is an attempt to give that flat data meaning and structure to the clients that interact with it.

A Collection of tools

So when you get down to it, AJAX is a technique, but more recently it has been able to define itself a little further due to the introduction a of a few specific programming tools mad available. Most specifically these include the XMLHttpRequest, DOM, and JavaScript and we'll we cover the use and interaction of these tools specifically later in the lecture.

History of interaction on the web

TThe surprising thing to most is that AJAX is really not a new thing. Developers have long been using tricks to asynchronously make requests. Javascript across XML is mostly a new technique but the achieved results are essentially the same. If you have ever created a framed site where frames have interacted with each other via javascript you have at a very basic level accomplished a form of AJAX.

Using javascript for application development

Most teams take on AJAX as a technique for large scale projects, that is to say - web software. Before getting involved it is important to think critically about the architecture and framework that your javascript will provide for you. Because javascript is a scripted rather than compiled language the enforcement of standards is much harder, and as such poor code is often propagated.