Significance of "my": It has a measurably distinguished behavior distinct from "our". Most notably useful in Modules.

Pay attention to the value of $TRUE in the sample:

This is t2.pm:

#!/usr/bin/perl

use strict;

package t2;

# --------------------------------------------------------------------
+----------
# Constants (Operationally, if not technically)
# --------------------------------------------------------------------
+----------

our    $RET_SUCCESS        = 0;
our    $RET_FAILURE        = (-1);
our    $RET_FATAL            = (-2);

my    $TRUE    = 1;
my    $FALSE    = 0;


# --------------------------------------------------------------------
+----------
# version() - Returns the version number of this module
# --------------------------------------------------------------------
+----------

sub version
{
    return sprintf "0.10a";
}


# --------------------------------------------------------------------
+----------
# Perl modules MUST return true
# --------------------------------------------------------------------
+----------

1;

__END__
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This is t3.pl:

#!/usr/bin/perl

use strict;

use t2;

print "our:  \$t2::RET_FAILURE = '$t2::RET_FAILURE'\n";
print " my:  \$t2::TRUE        = '$t2::TRUE'\n";

exit;

__END__
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