Introduction:
In this article,i am trying to explore how to configure and use updatepanel control in asp.net 2.0 applications.

Main:
Updatepanel is the one of the coolest control invented by asp.net 2.0 extensions,
and it will provide full support to all browsers,

When ASP.NET, a postback occurs, which takes form elements and various other pieces of information, sends it to the web server, the web server processes it, formats a page of data, and then sends the result back to the client. Along with this processing, the user notices several things:

Processing at the client tends to stop. Even if the user attempts to change a form element, the change is not reflected in what is sent to the web server. The result is that the page that is returned is based on what the form elements looked like at the moment the form submission occurred.

When the data returns from the web server, there is typically a “flash” of the browser’s screen and the user is redirected to the top of the web page, thus typically losing the context of where they are in the application. For pages that are less than one screenful of information, this is not a big deal. For larger pages, this can become a significant issue.

If the processing at the server takes a significant time, the user may become frustrated.

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Conclusion:
Hope this helps,
Happy coding.