ASP
• Classic ASP uses vb script for server side coding. Vb Script is not supported any more in ASP.NET.
• In classic ASP, there was no server controls. You have to write all html tags manually.
• All ASP pages are interpreted when the page is executed.
• Classic ASP uses a technology called ADO to connect and work with databases.

ASP.Net
• ASP.NET offers a very rich set of controls called Server Controls and Html Controls. It is very easy to drag and drop any controls to a web form.
• ASP.NET uses modern .NET languages like C#, VB.NET etc. They can be compiled to efficient Microsoft Intermediate Language (MSIL). When you compile an ASP.NET application, the server side code is compiled to assemblies. These assemblies are loaded at run time which makes the ASP.NET pages performance better than classic ASP.
• ASP.NET uses the ADO.NET technology .

In ASP.Net it is very easy to drag and drop a button control and double click on the button to write the event handler for the button click event. When you click on the button at turn time, it will execute whatever code you have written in the event handler.
This type of event driven programming was not available with classic ASP. You cannot drag and drop a button and write a 'click' event handler with ASP.