ASP.NET providing fully organized event divan code model for its users and In this model you can add control to web form and then can decided what event need to trigger. Each event handler is a discrete mechanism which keeps the page tidy and organized. Lets we looks around how ASP.NET code model work When our page run first time it will create page and control object, the initialize code execute, and then page is render to HTML and send it to client side. After reach web page to client side, page get the users feed backs like click submit button then reach to ASP.NET server side back In the side of sever now compare the page with the state which it had before send to the client. After understanding the difference it will trigger some action in the side of server like DB update operation Finally modify the page and render the html code and send it to client side. This same process will continue from step to over and over again according to the client reaction. Actuall