membuat timer dengan jquery

<!DOCTYPE html>
<html>
<head>
<title></title>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.6.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript">
jQuery(document).ready(function() {
var sec = 10
var timer = setInterval(function() {
   $("#mdtimer span").text(sec--);
   if (sec == 0) {
$("#makingdifferenttimer").delay(1000).fadeIn(1000);
$("#mdtimer").hide(1000) .fadeOut(fast);}
},1000);
});
</script>

</head>
<body>


<center>

<div id="makingdifferenttimer" style="display: none;">
<h1>Tampilan setelah loading timer</h1>
</div>

<div id="mdtimer">
<h1>Tampilan saat loading timer</h1>
<b>Please Wait <span>10</span> seconds</b>
</div>

</center>


</body>
</html>