I firmly believe that we should all switch to PERL.

Found in /usr/lib/perl5/5.6.0/pod/perlfaq1.pod

What's the difference between ""perl"" and ""Perl""?

One bit. Oh, you weren't talking ASCII? :-) Larry now
uses "Perl" to signify the language proper and "perl" the
implementation of it, i.e. the current interpreter. Hence
Tom's quip that "Nothing but perl can parse Perl." You
may or may not choose to follow this usage. For example,
parallelism means "awk and perl" and "Python and Perl"
look OK, while "awk and Perl" and "Python and perl" do
not. But never write "PERL", because perl isn't really an
acronym, apocryphal folklore and post-facto expansions
notwithstanding.