AJAX Definition-
AJAX (Asynchronous JavaScript and XML) is a web development technique for creating interactive web based applications that can asynchronously interchange data between server and client
How it works?
When an application uses AJAX, a new layer is added to the communication model. In the classic web application, communication between the client (the browser) and the web server were performed directly, using HTTP requests.
When the visitor requests a page, the server will send the full HTML and CSS code at once. After the visitor fills in a form and submits it, the server processes the information and rebuilds the page. It then sends the full page back to the client. And so on.
When using AJAX, the page is loaded entirely only once, the first time it is requested. Besides the HTML and CSS code that make up the page, some JavaScript files are also downloaded: the AJAX engine. All requests for data to the sever will then be sent as JavaScript calls to this engine. The AJAX engine then requests information from the web server asynchronously. Thus, only small page bits are requested and sent to the browser, as they are needed by the user. The engine then displays the information without reloading the entire page. This leads to a much more responsive interface, because only the necessary information is passed between the client and server, not the whole page. This produces the feeling that information is displayed immediately, which brings web applications closer to their desktop relatives.
Use of AJAX to reduce network traffic is spreading fast, especially in regions where customers and clients aren't always able to access applications over broadband connections.
At glance, AJAX may seem best suited for consumer-facing applications. Google Maps, Gmail, New Rediffmail, New Yahoomail are all fine examples of how AJAX can add some glitz to a Web site's UI. For enterprise applications, however, it can be difficult to see how AJAX can provide enough real benefit to offset the risks involved in adopting a new, complex form of Web development.Labels: AJAX, Development, Web |
