Internet Information Services 6.0 (herein IIS6) is Microsoft's web-server application, it runs only on Microsoft Windows 2003. FastCGI permits properly designed scripts to execute without the the overhead of starting up the interpreter on each HTTP request. This wikibook functions to teach the user how to configure IIS6 with FastCGI.
IIS does some non-http serving stuff as well, it bundles in FTP, and SMTP server applications (which can be uninstalled or disabled) and it largely relies on Windows or WINS servers for authentication. As an alternative to IIS-as-a-webserver on Windows, one can migrate away from IIS, and install Apache 2.x; or, the newer Lighttpd 1.4x or greater. Both, of the above web-servers also run on *nix and are freely available under more liberal licenses.