function reverse (str) { if (str === "") { return ""; } else { return reverse(str.substr(1)) + str.charAt(0); } } code example

Example 1: javascript reverse a string

function reverseString(s){
    return s.split("").reverse().join("");
}
reverseString("Hello");//"olleH"

Example 2: reverse a string javascript

var s = userInput[0];
var rev = [];
for(let i=0;i<s.length;i++)
{
    rev.push(s[s.length-1-i]);
}
console.log(rev.join(""));