ATL Server Question:

The Web server receives requests from the client and passes them on to the ISAPI extension DLL when the request is for a file extension handled by that DLL.

The ISAPI extension DLL receives requests from IIS and passes them on to the appropriate Web application DLL.

Web application DLLs provide application-specific functionality for handling requests and generating responses.

Server response files are text files that contain the static parts of a response and special tags describing where request handler methods can be called to generate the dynamic parts of the response.