The following code shows how to add icon to navbar, file/cut/edit/paste icon.
<!DOCTYPE html>
<html>
<head>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.0/css/bootstrap-combined.min.css">
<script type='text/javascript'
src="http://netdna.bootstrapcdn.com/twitter-bootstrap/2.3.0/js/bootstrap.min.js"></script>
<link rel="stylesheet" type="text/css"
href="http://netdna.bootstrapcdn.com/font-awesome/3.0.2/css/font-awesome.css">
</head><!-- w ww.ja va 2s .c o m-->
<body>
<div class="navbar">
<div class="navbar-inner">
<ul class="nav">
<li class=""><a href="#"><i class="icon-file"></i> New File</a></li>
<li><a href="#"><i class="icon-cut"></i> Cut</a></li>
<li><a href="#"><i class="icon-edit"></i> Edit</a></li>
<li><a href="#"><i class="icon-paste"></i> Settings</a></li>
</ul>
</div>
</div>
</body>
</html>