After the second, @arr contains three elements. After the first, @arr contains one element, which would be an arrayref.

#!/usr/bin/perl -w

use strict;
use Data::Dumper;

my @a = [ qw(a b c) ];
print "\@a contains ",scalar @a," element(s) and looks as such:$/",Dum
+per(\@a);

my @b = ( qw(a b c) );
print "\@b contains ",scalar @b," element(s) and looks as such:$/",Dum
+per(\@b);
__DATA__
output:
@a contains 1 element(s) and looks as such:
$VAR1 = [
          [
            'a',
            'b',
            'c'
          ]
        ];

@b contains 3 element(s) and looks as such:
$VAR1 = [
          'a',
          'b',
          'c'
        ];
[download]

Some places to look: perldata, perldsc, perllol, and qw. Hope this helps.

antirice    
The first rule of Perl club is - use Perl
The ith rule of Perl club is - follow rule i - 1 for i > 1