second.html

<!DOCTYPE html>

<html>
	<head>
		<title>Second app</title>
		<meta charset="utf-8">
		<script src="jquery-1.11.0.min.js"></script>
		<script src="jquery-migrate-1.2.1.min.js"></script>
		<script src="second1.js"> </script>
		<link rel="stylesheet" type="text/css" href="second.css"/>
	</head>
	<body>
		<input type="text" placeholder="this will disappear" id="abc">
		<p id="message"> </p>
		<ul>
			<li>
			Lucy
			<input type="checkbox" value="true"><br>
			</li>
			<li>
			Sarah
			<input type="checkbox" value="true"><br>
			</li>
		</ul>
		<div>
			<button id="first">
				Add
			</button>
			<button id="second">
				Remove
			</button>
		</div>
	</body>
</html>