Images below the fold (the ones lower than window bottom) are not loaded. When scrolling down they are loaded when needed. This example uses additional possibility of putting placeholder image to src attribute already in html. Real image url is stored in original property. This is not needed but gives additional speed increase. Shift-reload to test again. Compare this to page where plugin is disabled or page with larger images.
<img original="img/example.jpg" src="img/grey.gif">
$("img").lazyload({
placeholder : "img/grey.gif"
});
