Data Type Php

$twister = "Peter Piper picked a peck of pickled peppers";
print("$twister
");
$letter_array = count_chars($twister, 1);
while ($cell = each($letter_array)){
  $letter = chr($cell['key']);
  $frequency = $cell['value'];
  print("Character: '$letter'; frequency:  $frequency
");
}
?>