could you explain the function in javascript?
<blockquote>
  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/3921922/what-does-this-mean-function-x-y-a-b-in-javascript">What does this mean? (function (x,y)){&hellip;}){a,b); in JavaScript</a>  </p>
</blockquote>



<pre><code>(function(){
    var foo = 'Hello world';
})();
</code></pre>

<p>i don't know what's use of it? and what's meaning of it/?</p>
