What is (function($) {...}) (jQuery)?
<p>I am a javascript newbie and recently came into the following code.</p>

<pre><code>(function($){

    if(!document.defaultView || !document.defaultView.getComputedStyle){
        var oldCurCSS = jQuery.curCSS;
        jQuery.curCSS = function(elem, name, force){
            if(name !== 'backgroundPosition' || !elem.currentStyle || elem.currentStyle[ name ]){
                return oldCurCSS.apply(this, arguments);
            }
            var style = elem.style;
            if ( !force &amp;&amp; style &amp;&amp; style[ name ] ){
                return style[ name ];
            }
            return oldCurCSS(elem, 'backgroundPositionX', force) +' '+ oldCurCSS(elem, 'backgroundPositionY', force);
        };
    }
})(jQuery);
</code></pre>

<p>What is <code>function($) {...} (jQuery)</code>?</p>

<p>PS: I also don't quite get what the code is for... If possible please give a hint on it.</p>
