Several months ago some monks advised me to start using CGI.pm, which is built in to current versions of Perl. One thing which CGI.pm does very well is producing the http header and boilerplate HTML required for displaying output. In this case, using CGI.pm would have solved the part of the problem caused by the typo in the http header.

To use CGI.pm add:

use CGI qw/:standard/;
  print header,
        start_html('A Simple Example');
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Then add your application-specific HTML. End your page with the statement

print end_html;
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A programmer named Lincoln D. Stein who approaches Larry-hood in his good works wrote this module. You can read his documentation for it here.