<!Doctype html>
<html>
<head>
<meta charset="utf-8">
<style>
b {marginLeft:2pt;}
</style>
</head>
<body>
<div id="first">test 1 </div>
<div id="second">test 2</div>
<script type="text/javascript">
var f = document.getElementById("first");
var s = document.getElementById("second"); var r;
var time1 = new Date().getTime();
for (i = 0 ; i < 1000; ++i){
f.innerHTML += "<b>A da</b>";
}
var time2 = new Date().getTime();
var time3 = new Date().getTime();
for (i = 0 ; i < 1000; ++i){
r = document.createElement ("b");
r.innerHTML = "A da";
s.appendChild (r);
}
var time4 = new Date().getTime();
alert ("(innerHTML +=)милисек = " + (time2 - time1) );
alert ("(appendChild)милисек = " + (time4 - time3) );
alert ("коффицент" + ((time2 - time1) / (time4 - time3)) );
</script>
</body>
</html>