it's sort-of a subclass of CGI. it provides you a way to *organize* your run-modes ( actions ) in your application with a defined set of parameters and matching subroutines. something like:

"foo_action" => \&foo(),
"bar_action" => \&bar()
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sub foo {
   my $self = shift;
   # do stuff
}
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Oh, BRILLIANCE.

Does it allow you to take query parameters to match your subroutines?

"and I wonder, when I sing along with you if everything could ever feel this real forever? if anything could ever be this good again? the only thing I'll ever ask of you, you've gotta promise not to stop when I say 'when'", she sang

here's part of a setup method ( i'm working on the project right now ) :

sub setup {
                my $self = shift;
                $self->{TEMPLATEDIR} = "/home/templates";
                $self->start_mode('edit_setup');
                $self->mode_param('rm');
                $self->run_modes(
                        'setup'         => \&setup_list,
                        'edit_setup'    => \&setup_edit,
                        'view_listing'  => \&view_listing,
}
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the start_mode determines what the first value of your run_mode will be.

subs are then executed by URLs like:  index.cgi?rm=view_listing

now go read the  perldoc on it. ;-)