Is it obvious the person isn't wearing any clothing?

If yes, please use the nudity flag.

How does this work in practice?

I like the analogy of walking down the street - if someone saw that much of you on the street, would the cops arrest you for indecent exposure? In this case, think of it as posing next to a window without curtains. What would be seen from the outside?

Facial shots - no nudity tag needed. No one can tell if the person is wearing clothing or not.

Upper body shots (the hips and below aren't visible), for men, no nudity tag is necessary. For females, please use the nudity tag if the breasts and nipples are clearly shown. (Topless in public is against the law in most areas of the U.S. for women.) Please don't ask exactly how many pixels can be flesh before it's considered nudity. We're trying for common sense and courtesy, not inflexible and arbitrary numbers.

Full body - unless the crotch is covered (and the nipples as well for women) by clothing or a prop then it's a nude shot. (Yes, fig leaves do count, though it could still get you arrested in many areas of the world.)

This isn't meant to surpress anyone's rights, say that nudity is evil, etc. It's meant as a compromise. Not everyone wants to view nude pictures, or they may be in a situation where viewing nudity at that time is inconvenient, and we want to accomodate them but we also don't want to ban nudity or shove it into some small corner of the site. Nudity in artwork is a time honored tradition that we're not about to go against. We're simply making a compromise so as many people as possible can use this site.

I don't consider this any different than the idea of smoking and non-smoking sections in a restaurant. If you want to smoke, please do not sit in the non-smoking area and light a cigarette. If you don't smoke, please don't sit in the smoking area and complain about the fumes. And smoking heroin is against U.S. law, so it's not allowed in any part of the restaurant!

Hope this helps,

Cres