Externally load html with Jquery

Is it possible to externally load an html file into another with the use of a Jquery script? I’ve looked on Jquery’s site and found the Partial .load function but it doesn’t seem to work, maybe I’m writing it wrong.

<html>
	<head>
		<script type="text/javascript" src="https://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js"></script>
		<script>
			$("#search_box").load("topbar.html");
		</script>
	</head>
	<body>
		
		<div id="search_box">
			
		</div>
	</body>
</html>

Maybe Jquery isn’t the approach I’m looking for, if that’s the case what would be the best way to externally load an html file through client-side methods?