You are actually better off wearing very light (both in color and weight) clothes that completely cover you when it's hot out. Shorts and tee shirts (or nudity) are not as effective at keeping you cool even though you might think they would be; a burnt body does not dissipate heat efficiently.
I think clothing primarily came as a way to protect sensitive areas from the elements. Primitive man started wearing loin cloths to protect their reproductive areas from anything that might be a danger to them. Go forward tens of thousands of years, and people start wearing clothing as a sign of social status. Nowadays, I think the main the main reason is because its always been that way. Because of that, we have come to see nudity as obscene, even though it isn't in the slightest. Modern society is also a bad influence to our children, teaching them that the human body is a bad thing.
It really is detrimental to our society, but it is not going to change anytime soon.
On a somewhat unrelated note, I feel this thread would be more appropriately suited (no pun intended) to the Mature Discussion forum.
Well it protects the skin to a certain point. Just the matter of opinion. I wear clothes no matter what even if we don't but thats just me being uncomfortable with my body. And i'd prefer if my niece wore her clothes so no child molester tried anything. And some guys are just plain pervs enough.
Maybe some people arent as confident of their body as u may be, not saying im one of them, hell i would love to go naked everywhere if everybody else would do the same, but still might not be the greatest of ideas.