Разбери простейшие примеры, для начала:
Code
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>jQuery demo</title>
</head>
<body>
<a href="http://jquery.com/">jQuery</a>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.5/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("a").click(function(event){
alert("As you can see, the link no longer took you to jquery.com");
event.preventDefault();
});
});
</script>
</body>
</html>
второй - простой пример с "hide":Code
<!DOCTYPE html>
<html>
<head>
<style>
p { background:#dad; font-weight:bold; }
</style>
<script src="http://code.jquery.com/jquery-latest.js"></script>
</head>
<body>
<button>Hide 'em</button>
<p>Hiya</p>
<p>Such interesting text, eh?</p>
<script>
$("button").click(function () {
$("p").hide("slow");
});
</script>
</body>
</html>