I have an ASPX page .In the Top i am displaying 5 categories (Ex : Pen,Book,Shoe,Mobile,Mirror) When i click on any of the categories,I want to show the products under that
You could also consider a "quick and dirty" solution: in your page code-behind, implement ICallbackEventHandler, and return a block of html, which you stuff into your div or table.
Update: Take a look at http://msdn.microsoft.com/en-us/library/ms178208.aspx for additional details on what you need to implement this.