Reverse a string with JavaScript

reverse.js

//Using built-in functions
function reverseString(str) {
  return str.split("").reverse().join("");	
}

//Without built-in functions
function reverseString(str) {
    var newString = "";
    for (var i = str.length - 1; i >= 0; i--) {
        newString += str[i];
    }
    return newString;
}