ASP.NET is a server-side web application framework that allows developers to build dynamic web pages using .NET languages like VB.NET and C#. It is different from classic ASP in that it uses fully-fledged programming languages rather than scripting. ASP.NET pages consist of code behind files that contain the programming logic and are compiled into classes. These classes generate HTML sent to browsers using ASP.NET server controls. The .NET Framework provides a common language runtime, type system, and class libraries for all .NET languages.