How to use dialogbox in plain html?

I am trying to use Jquery in plain HTML, but in doing so I am unable to execute it. I think I am missing some link

Header

<script src="http://ift.tt/1mWWrGH">      </script>
<link rel="stylesheet" href="//code.jquery.com/ui/1.11.2/themes/smoothness/jquery-ui.css">
<script src="//code.jquery.com/ui/1.11.2/jquery-ui.js"></script>
<script src="http://ift.tt/18QkLne"></script>

Script

 $( document ).ready(function() {
     $("#btnShare").click(function(){
         alert("Click executed");
         $( "#menu" ).menu();
     });
 });

Bottom I am having some code with <li> and <ul>.

I am trying this code in Notepad++ . I am able to get alert . Can anyone help me.

Any help is helpful.