Can someone explain this Jquery
<pre><code>$(document).ready(function () {
    if ((screen.width &gt;= 1024) &amp;&amp; (screen.height &gt;= 768)) {
        alert('Screen size: 1024x768 or larger');
        $("link[rel=stylesheet]:not(:first)").attr({
            href: "style2.css"
        });
    } else {
        alert('Screen size: less than 1024x768, 800x600 maybe?');
        $("link[rel=stylesheet]:not(:first)").attr({
            href: "style1.css"
        });
    }
});
</code></pre>

<p>I'm not getting this part: <code>$("link[rel=stylesheet]:not(:first)").attr</code></p>
