Normally the first thing you will do in any CGI script is print out an HTTP header. This tells the browser what type of document to expect, and gives other optional information, such as the language, expiration date, and whether to cache the document. The header can also be manipulated for special purposes, such as server push and pay per view pages.

        print $query->header(-type=>'image/gif',
                             -nph=>1,
                             -status=>'402 Payment required',
                             -expires=>'+3d',
                             -cookie=>$cookie,
                             -charset=>'utf-7',
                             -attachment=>'foo.gif',
                             -Cost=>'$2.00');<div class="pmsig">
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And I am a better monk for it.

Hopefully, it remains to be seen (we'll have to wait for your future questions).