What does the ! part of !function(){...}(); mean?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/3755606/what-does-the-exclamation-mark-do-before-the-function">What does the exclamation mark do before the function?</a>  </p>
</blockquote>



<p>So I've come across the use of the following by the twitter share button code:</p>

<pre><code>!function (d, s, id) {
    var js, fjs = d.getElementsByTagName(s)[0];
    if (!d.getElementById(id)) {
        js = d.createElement(s);
        js.id = id;
        js.src = "//platform.twitter.com/widgets.js";
        fjs.parentNode.insertBefore(js, fjs);
    }
}(document, "script", "twitter-wjs");
</code></pre>

<p>And I was just wondering what the <code>!function</code> bit does.</p>

<p>I'm guessing is short for <code>(function(){...})();</code> but I couldn't find anything online to confirm it.</p>
