Visual InterDev
An Active Server Page (ASP) file that includes server script to be executed by Microsoft® Internet Information Server (IIS). The .asp extension on the file alerts the server that it should process the file before sending it to the browser. After the server script in an .asp file has been processed by the server, the file is sent to the browser, in the same manner as an .htm file.
For more information, see Introducing Active Server Pages.