&viewThumbnails(\@array1, \@array2);

# and then your subroutine looks like:

sub viewThumbnails {
    my ($firstset, $secondset) = @_;
    # do something with these arrayrefs
}

##</code><code>##

my ($zero, $one, $two) = @_;

##</code><code>##

my $zero = @_[0];
my $one = @_[1];
my $two = @_[2];

##</code><code>##

my $firstarg = shift;