기본내장객체 - Math

 <script type="text/javascript">
        var a = -200;
        var b = 30;
        var c = 21.5;
        var abs = Math.abs;
        var max = Math.max;
        var min = Math.min;
        var random = Math.random;
        var round = Math.round;

        alert(abs(a));
        alert(max(a, b, c));
        alert(min(a, b, c));
        alert(random());
        alert(round(c));
    </script>