Frequently Asked Question
It also ensures those static resources are distributed globally to fast static servers closer to the clients, wherever they are Worldwide. It is pretty damn good at that but it also has to ensure it does not break a website when doing that. So for URLs that it can be certain which can be replaced with CDN urls, it performs this change.
Sorry for such a complicated explanation but in summary, the SharkGate CDN works for about 80% of a site on average (for a lot of sites nearer 95%) but there are some static files on a site that it cannot be fully sure about so it leaves them as is.