As I understand it.. Subroutines do not return arrays or hashes.
They can return one zero or more values, that at the receiving end can be sown together into an array/hash/whatever, making it seem like you returned an array or hash.

Some example code (untested.)..

my @array1 = ('Paula', 'Sherri', 'Cynthia', 'Ludovico');

my @gotback = names_a();
$gotback[0] = 'Jimmy';
# @array1 is still ('Paula', 'Sherri', 'Cynthia', 'Ludovico')

my $gotback = name_aref();
$gotback->[0] = 'Jimmy';
# @array1 is now ('Jimmy', 'Sherri', 'Cynthia', 'Ludovico')

my @gotback2 = @{ names_aref() }; # makes a copy
$gotback2[0] = 'Back to Paula'; 
# @array1 is still ('Jimmy', 'Sherri', 'Cynthia', 'Ludovico')
# because we made a copy by doing @{ names_aref() }



sub names_a {
  # this really returns 
  # 'Jimmy', 'Sherri', 'Cynthia','Ludovico'
  # and not @array1
  # when received at the other end, it may be slapped 
  # back togeter into an array, 
  # but it will be a new list (a new array)

  return @array1;
}

sub names_aref {
   # this returns a reference, therefore both what this is
   # returning and the original @array1 both point to the
   # same space in the symbol table (place in memory).  
  return \@array1;
}
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