JavaScript - Random function

Example 1: Change background color using random and setInterval function.

<script>
    setInterval(fun,200);
	
    function fun(){
        var r = Math.ceil(Math.random()*255);
        var g = Math.ceil(Math.random()*255);
        var b = Math.ceil(Math.random()*255);
        document.body.style.background = "rgb("+r+","+g+","+b+")";
    }
</script>