What actually does this javascript snippet mean?
<p>From <a href="http://html5boilerplate.com/mobile" rel="nofollow">HTML5 Mobile Boilerplate's</a> helper.js:</p>

<pre><code>(function(document){
    //all stuff here
})(document);
</code></pre>

<p>What does this snippet do or when does it run?</p>
