I'm writing a simple code using bootstrap for dropdown menu, the code seems fine. However, it doesn't expand when I clicked on the caret. I'm not sure what goes wrong. Can someone help me with this? Thanks for the help.
<!DOCTYPE html>
<html lang="en">
<head>
<title>thenewboston</title>
<meta charset="utf-8">
<meta name="viewpoint" content="width=device-width, initial-scale=1">
<!-- Latest compiled and minified CSS -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css" integrity="sha384-1q8mTJOASx8j1Au+a5WDVnPi2lkFfwwEAa8hDDdjZlpLegxhjVME1fgjWPGmkzs7" crossorigin="anonymous">
<!-- Optional theme -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap-theme.min.css" integrity="sha384-fLW2N01lMqjakBkx3l/M9EahuwpSfeNvV63J5ezn3uZzapT0u7EYsXMjQV+0En5r" crossorigin="anonymous">
<!-- Latest compiled and minified JavaScript -->
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js" integrity="sha384-0mSbJDEHialfmuBBQP6A4Qrprq5OVfW37PRR3j5ELqxss1yVqOtnepnHVP9aJ7xS" crossorigin="anonymous"></script>
</head>
<body>
<nav class="navbar navbar-inverse">
<div class="container-fluid">
<!-- Logo -->
<div class="navbar-header">
<a href="navbar.html" class="navbar-brand">ABE TECHNOLOGY</a>
</div>
<!-- Menu Items -->
<div>
<ul class="nav navbar-nav">
<li class="active"><a href="#">Home</a></li>
<li><a href="#">About</a></li>
<li><a href="#">Contact</a></li>
<!-- drop down menu -->
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown">My Profile <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Friends</a></li>
<li><a href="#">Photos</a></li>
<li><a href="#">Settings</a></li>
</ul>
</li>
</ul>
</div>
</div>
</nav>
</body>
</html>