ASP.NET 2.0 allows developers to configure whether a page compiles or not. Consider the following page directive:
<%@ Page Language="C#" CompilationMode="Never" %>
Setting the CompilationMode attribute to Never will disallow code on the page. It will also prevent compilation to an assembly. These pages can contain server controls or Expressions such as $AppSettings and $ConnectionStrings.
The main benefit is scalability. In large web sites, this can avoid the need to compile high number of pages into assemblies. Instead of compiling, these "no-compile" pages are processed by it's corresponding control builder which is preserved in memory for the life of the application.
You can also let ASP.NET determine if a page qualifies for "no-compile" automatically by making the following setting in web.config:
