Actionscript and asp.net

Can anyone give me a brief overview of ASP.NET ASP and ASPX? I have read things online and have my own impression, but most certainly it’s wrong. Another important question is: what does a webserver need to serve .asp and .aspx pages? because Im just making a web app using aspx embedded with flashmx04, i really had to know something about ado.net connectivity/SQL server 2000 just to make massive web apps using flash.

can anyone tell me

Thanks