What is the HTTP request steps when the client access SharePoint Web Application , Details Required ?

SharePoint is a ASP.Net application which runs on IIS servers. So its steps are not different than any other ASP.Net application. Please refer below 

http://www.dotnetcurry.com/showarticle.aspx?ID=747

http://msdn.microsoft.com/en-us/library/vstudio/bb470252(v=vs.100).aspx