Asynchronous JavaScript and XML, Ajax, is a web development technique, which was created for making interactive web applications with the help of:

It must be known that Ajax is not a technology itself, though it is a base for a group of technologies taken together.

To give all the necessary and sufficient information, let us examine the main advantages and disadvantages of using the Ajax development.

The Ajax applications work much faster than the other web applications and allow to create a new web interface design for your page.

Traditional web applications present forms that were completed by a user to a web server. The server accepts the forms and responds back by sending a new web page. As a result, the applications run much slower and more awkward, since the server is able to submit only the whole page at a time.

On the other hand, applications of the Ajax development can send requests to the web server and extract only the necessary information (generally with the help of XML-based web services dialect). Then, the JavaScript processes the web server response to the client.1

As you see, using the Ajax development you will be relieved from long expectations, since the data can be manipulated without rendering the entire page again in the web browser.

Thus, the amount of data, interchanged between the web browser and the web server, is reduced; the Web server processing time is saved, the interface becomes more apprehensible; a new web interface design astonishes with its liveliness and the client's demands are satisfied.

The major mistake of the Ajax development is that when a page is dynamically updated, the returning to the previous page may be impossible. The matter is that browsers generally record only static page visits in their history lists and in the case when a page has been modified dynamically, the browser does not have enough time to fix it properly. Hence, when a user wants to go back and clicks the back button, the applications of the Ajax development fails to undo the last change.

Consequently, it is necessary to provide fallback options for the users on other platforms or browsers, as most methods of the Ajax implementation rely on the features present in the desktop graphical browsers.

The developers of Ajax invented various solutions to this problem; however, the most part of the methods resolves the creation and usage of invisible I Frames, which allow to stimulate changes of the browser's "back history", restoring the application state that existed at the time.2

To come to a conclusion, the idea of the Ajax technology is very interesting, very popular and effective, since in the process of the Ajax usage, a user solves the problem of the Network latency (when the interval between the user's request and the server's response takes a lot of time), nevertheless, the technology still has to be worked over properly.