creationix/app.js

## app.js
function Box(width, height) {
  this.width = width;
  this.height = height;
}
Box.prototype.getArea = function () {
  return this.width * this.height;
}

var box = new Box(3, 5);

var area = box.getArea();

document.body.innerText = "The area is " + area;

## index.html
<!doctype html>
<html>
<head>
  <title>Sample Page</title>
  <link rel="stylesheet" href="style.css"/>
</head>
<body>
  <script src="app.js"></script>
</body>
</html>

## style.css
body {
  color: #faa;
  background-color: #333;
  font-size: 100px;
  text-align: center;
  padding: 40px;
}
	function Box(width, height) {
	this.width = width;
	this.height = height;
	}
	Box.prototype.getArea = function () {
	return this.width * this.height;
	}

	var box = new Box(3, 5);

	var area = box.getArea();

	document.body.innerText = "The area is " + area;
	<!doctype html>
	<html>
	<head>
	<title>Sample Page</title>
	<link rel="stylesheet" href="style.css"/>
	</head>
	<body>
	<script src="app.js"></script>
	</body>
	</html>
	body {
	color: #faa;
	background-color: #333;
	font-size: 100px;
	text-align: center;
	padding: 40px;
	}