Asp .Net Ajax has many ways to accomplish simple and complex web application requirement. As a brief Asp.Net Ajax has Server and Client Side development.
Often Server and Client Side mixed to make Ajax development more confinient.
Server side development process UI update by sending a response from server machine whereas Client side process all UI update on client or user machine side.
In development point of view, Server side code is simpler. But the process uses more resources on server machine. Client side code requires more Js scripting, so in the end our client script may be much longer than server side script.
Client side Ajax development is more suitable for web applications that have complex user interaction since its doesn’t consume server resouces to update the UI.
But off course, your app logic still remains on server side.
I use Microsoft Ajax Library to simplify client side development. This Ajax Library is a rich framework and used extensively at client script.
If you are new to Asp.Net Ajax then you should visit my previous posts about Ajax Server Controls. I explained and gave example of Asp .Net Ajax for Server side development. Please visit these Urls:Introduction To Asp .Net Ajax (ScriptManager, UpdatePanel, ContentTemplate, Triggers) and Introduction to Asp .Net Ajax – 2 (UpdateProgress).
At general, we have to include controls like
UpdatePanel with its child tag <ContentTemplate> and <Triggers>, and also
ScriptManager is must to enable Ajax request. UpdatePanel contains all control which will have Ajax Process and UpdateProgress acts as progress info to indicate that asynchronous process is still working.