So when I create a Perl script with the "use CGI" in the script and save this file as say "trialOfCGI.pl", will it be automatically marked as CGI script ? Or do we have to manually mark the script as CGI ? If we save the file with .cgi extension e.g. "trialOfCGI.cgi", does it mark the script as CGI script ? If thats the case, then every CGI script has to be marked with cgi extension only ? When do we use cgi extension for a script ? In the cgi-bin dir, can we put a script without .cgi extension ?