AJAX

AJAX stands for Asynchronous JavaScript and XML.It is a web development technique used for creating faster, interactive application.Instead of reloading the whole page everytime ,data which is necessary is exchanged behind the scenes with the server.For exchanging the data asynchronously XMLHttpRequest object is used.It is a type of language made popular by google in 2005.
If your are creating a Asp.Net application in Visual Studio 2005 then it is really easy to implement AJAX functionality.While using microsoft controls you have to first add ScriptManager and then place UpdatePanel control .Within this UpdatePanel control now if you add any web controls then it will act as AJAX.If you are using infragistic controls then we have to add WebAsyncRefreshPanel control and the web controls residing inside that WebAsyncRefreshPanel control will act as AJAX.