funtion that generate random words with random length using only letters and not numbers

function generateRandomWords(length) {
  var result           = '';
  var characters       = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
  var charactersLength = characters.length;
  for ( var i = 0; i < length; i++ ) {
     result += characters.charAt(Math.floor(Math.random() * charactersLength));
  }
  return result;
}

generateRandomWords(15)