Facebook - example of facebook pixel code

Question

<!-- Facebook Pixel Code -->
<script>
    !function (f, b, e, v, n, t, s) {
        if (f.fbq) return; n = f.fbq = function () {
        n.callMethod ?
        n.callMethod.apply(n, arguments) : n.queue.push(arguments)
        };
        if (!f._fbq) f._fbq = n; n.push = n; n.loaded = !0; n.version = '2.0';
        n.queue = []; t = b.createElement(e); t.async = !0;
        t.src = v; s = b.getElementsByTagName(e)[0];
        s.parentNode.insertBefore(t, s)
    }(window, document, 'script',
        'https://connect.facebook.net/en_US/fbevents.js');
    fbq('init', 'xxxxxx');
    fbq('track', 'PageView');
    </script>
    <noscript>
        <img height="1" width="1" src="https://www.facebook.com/tr?id=xxxxxx&ev=PageView
            &noscript=1" />
    </noscript>
<!-- End Facebook Pixel Code -->