For kael: FastCGI starts you CGI (not only perl, but who needs something else) as a seperate process. Apache with the FastCGI module than communicates trough a socket (or even IP) with this CGI process. The benefit is, as Randal said, that the Webserver doesn't have to spawn a new process for every request.

FastCGI is a good way, if you just want you CGIs to be faster (referring to the startup time) and don't like to "bother" with mod_perl. For everything else, mod_perl is the way to go.

Roli