comment your code like this

Constant Limit = 1000; %Sufficient digits.
Constant Base = 10; %The base of the simulated arithmetic.
Constant FactorialLimit = 365; %Target number to solve, 365!
Array digit[1:Limit] of integer; %The big number.
Integer carry,d; %Assistants during multiplication.
Integer last,i; %Indices to the big number's digits.
Array text[1:Limit] of character;%Scratchpad for the output.
Constant tdigit[0:9] of character = ["0","1","2","3","4","5","6","7","8","9"];
BEGIN
digit:=0; %Clear the whole array.
digit[1]:=1; %The big number starts with 1,
last:=1; %Its highest-order digit is number 1.
for n:=1 to FactorialLimit do %Step through producing 1!, 2!, 3!, 4!, etc.
carry:=0; %Start a multiply by n.
for i:=1 to last do %Step along every digit.
d:=digit[i]*n + carry; %The classic multiply.
digit[i]:=d mod Base; %The low-order digit of the result.
carry:=d div Base; %The carry to the next digit.
next i;
while carry > 0 %Store the carry in the big number.
if last >= Limit then croak("Overflow!"); %If possible!
last:=last + 1; %One more digit.
digit[last]:=carry mod Base; %Placed.
carry:=carry div Base; %The carry reduced.
Wend %With n > Base, maybe > 1 digit extra.
text:=" "; %Now prepare the output.
for i:=1 to last do %Translate from binary to text.
text[Limit - i + 1]:=tdigit[digit[i]]; %Reversing the order.
next i; %Arabic numerals put the low order last.
Print text," = ",n,"!"; %Print the result!
next n; %On to the next factorial up.
END;

Constant Base = 10; %The base of the simulated arithmetic.
Thank you for this comment, I wasn't sure what else could Base be!

digit:=0; %Clear the whole array.
I didn't know that either! I would have never guessed!

Instead, I think you should comment your code like this
#!/usr/bin/perl
use strict; # PERL by Example (2015) p. 77
use warnings; # PERL by Example (2015) p. 85
# use Encode; # 2016feb16: http://perldoc.perl.org/perlunitut.html
# use utf8; # 2016feb16: for Cyrillic Russian characters
# use feature "unicode_strings"; # 2016feb16: Perl_Programming/Unicode_UTF-8
# binmode STDIN, ":encoding(UTF-8)"; # 2016feb16
# ghost155.pl being coded on Sun.1.MAY.2016 or later
# Please host the Ghost AI and install it for other persons.
# http://doc.perl6.org/language/variables
our $. = 0; # 2016jan14: line counter variable; PbyX 299
our $_ = " "; # 2016jan10: hidden variable; P_by_Ex p. 301
our $abc = ""; # AudBuffer() transfer character;
our $act = 0; # 2016jan16: quasi-neuronal activation-level
our $actbase = 0; # 2016jan23: AudRecog discrimination activation base
our $actpsi = 0; # 2016apr11: psi from which activation is to be spread
our $age = 0; # 2015apr26: Temporary age for loop-counting.
our $aud = " "; # 2016jan28: explicit package from @ear array
our $audbase = 0; # 2016jan27: recall-vector for VerbGen()
our $audbeg = 0; # 2016jan17: auditory-beginning tag for start of word.
our $audjuste = 0; # 2016feb12: NounPhrase motjuste aud to Speech() module
our $audnew = 0; # 2016jan17: holds onset-tag while rest of word comes in.
our $audpsi = 0; # 2016feb12: concept number of word in @ear array
our $audrec = 0; # 2016jan23: auditory recognition concept-number
our $audrv = 0; # 2016feb12: auditory recall-vector for Speech()
our $audrun = 1; # 2016jan26: counter of loops through AudRecog()
our $b01 = ""; # 2016apr02: for OutBuffer();
our $b02 = ""; # 2016apr02: for OutBuffer();
our $b03 = ""; # 2016apr02: for OutBuffer();
our $b04 = ""; # 2016apr02: for OutBuffer();
our $b05 = ""; # 2016apr02: for OutBuffer();
our $b06 = ""; # 2016apr02: for OutBuffer();
our $b07 = ""; # 2016apr02: for OutBuffer();
our $b08 = ""; # 2016apr02: for OutBuffer();
our $b09 = ""; # 2016apr02: for OutBuffer();
our $b10 = ""; # 2016apr02: for OutBuffer();
our $b11 = ""; # 2016apr02: for OutBuffer();
our $b12 = ""; # 2016apr02: for OutBuffer();
our $b13 = ""; # 2016apr02: for OutBuffer();
our $b14 = ""; # 2016apr02: for OutBuffer();
our $b15 = ""; # 2016apr02: for OutBuffer();
our $b16 = ""; # 2016apr02: for OutBuffer();
...

sub TabulaRasa() { # 2016jan25: Establish size and emptiness of CNS.
print "Size of AI memory is $cns human language code = $hlc \n"; #2016feb16
my $trc = 0; # 2015apr2015 $trc is "tabula rasa counter".
until ($trc == $cns) { # 2015apr26 PbEx5e p. 193 "Loops".
$psy[$trc] = "0,0,0,0,0,0,0,0,0,0,0,0,0"; # 2016mar26: adding $iob.
$ear[$trc] = " ,0,0"; # 2016jan28: initialize three columns.
$trc++; # 2015apr26: Increment tabula-rasa-counter $trc.
} # End of loop filling auditory memory with blank engrams.
} # 2016feb11: End of TabulaRasa "clean slate" sequence.
...

# 2015may28 Requirements of Speech mind-module:
# Speech module shall output a single word starting at given @ear point.
# Outputted word shall be fed internally into the ReEntry module.
# Inflected nouns and verbs shall be spoken from NounGen or VerbGen.
sub Speech() { # 2016feb12: output of a word as text or sound
if ($age > $cns) { die "TERMINATING: memory full \n"; } # 2016jan28
$t2s = $aud; # 2016feb13: start from the auditory recall-vector $aud
do { # PERL by Example (2015), p. 194: do/until Loops
my @aud=split(',',$ear[$t2s]); # 2016jan28: expose @ear values
$output = "$output" . "$aud[0]"; #2016apr09: commenting back in
# $output eq "$output" . "$aud[0]"; #2016apr25
if ($t2s == $aud) { print "\N{U+00}" } # 2016apr04: TEST, FOR UNICODE
print "$aud[0]"; # 2016mar29: say each character
$idea = "$idea" . "$aud[0]"; #2016apr09: concatenate for re-entry
$pov = 1; # 2016apr08: internal point-of-view during thinking.
$t2s++ ; # 2016mar10: Increment time-to-speech to advance thru memory.
# if ($aud[0] eq " ") { # 2016jan28: if no character is found
if ($aud[0] eq " ") { # 2016apr29: if no character is found
$audrv = $t2s; # 2015may13: Prepare for next word in memory.
return; # 2015may13: Exit at end of a word
}; # 2015may13: End of if-clause
} until $t2s eq $cns; # Show the whole array of AI Mind memory.
$phodex = 1; # 2016apr03: reset for AudBuffer()
} # http://mind.sourceforge.net/speech.html