Just few minutes ago, i was viewing some pictures of my friend , but i don't know whats wrong with facebook advertisement system or what else,  the nude picture came up without any warnings and  completely looks like a Porn Ads. I think facebook is believe to be a clean and safe social network site. ThankGod i was not with my family at that time. Here is the attached screen capture .just Sharing guys and be careful what may else come up to your screen.