Script manger vs Updatepanel

your question doesn't make any sense , my suggestion to you is first learn the basic concepts of .Net and Abstract classes , base classes, interfaces
then ScriptManager all those things.
Be friendly with google and you will get every information there.
following urls are are good to refer:
http://msdn.microsoft.com/en-us/library/sf985hc5%28v=vs.71%29.aspx[^]

http://www.programcall.com/27/csnet/abstract-classes-and-abstract-methods-in-csnet.aspx[^]

http://msdn.microsoft.com/en-us/library/system.web.ui.scriptmanager.aspx[^]

http://www.aspxcode.net/free-asp-net-ajax-source-code.aspx?Topics=How%20to%20Use%20ScriptManager[^]