Reverse string in javascript

String.prototype.reverse1 = function(){
    return this.split("").reverse().join("");
}


String.prototype.reverse2 = function(){
    var i, j=0, reversed = "";
    var ttmp=new Array();
    for (i = this.length-1; i >= 0; i--) {
        ttmp[j++] = this.charAt(i);
    }
    return ttmp.join("");
}


String.prototype.reverse3 = function(){
    var i, reversed = "";
    for (i = this.length-1; i >= 0; i--) {
        reversed += this.charAt (i);
    }
    return reversed;
}