eq(index) returns the element position in matched elements starts at 0 and goes to length - 1.
<html>
<head>
<script type="text/javascript" src="js/jquery-1.3.2.js"></script>
<script type="text/javascript">
$(document).ready(function(){
$("div").eq(2).css("color","blue");
});
</script>
<style>
.selected { color:red; }
.highlight { background:yellow; }
</style>
</head>
<body>
<body>
<div id="single">asdf</div>
<div id="single">asdf</div>
<div id="single">asdf</div>
<div id="single">asdf</div>
</body>
</html>
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