jquery

To use JQuery,

I added <?php wp_enqueue_script(“jquery”); ?> before wp_head()

And I put some code from a JQuery tutorial:

<center id="AreaBox">
	<div id="ButtonBox">
		<input type="button" name="bt" value="ID" />
		<input type="button" name="bt" value="Element" />
	</div>
	<div class="MsgBox">
	</div>
</center>

<script language="javascript">
$("input:button").css("width","100").css("height","100").click(function(){
   alert("Button clicked");
});
$.modal('<p><b>HTML</b> elements</p>');
</script>

But the code in <script> does not work.. What did I miss?