Why did Superman wear his frilly red underthings on the outside of his body stocking? The fine folks at Today I Found Out offer this simple, sensible explanation.

Technically the answer is they do not wear their underwear on the outside. If it's on top, then whatever is underneath it becomes underwear, so really their super-clothes are in the right place, if not particularly fashionable.

I always figured Superman did it to keep people from focusing on how much he looks like Clark Kent. "You know who you look like... whoa, what's with the red panties?"

But no, as the TIFO folks explain, it's because circus performers had no idea how to wear shorts, and it infected comics.

This helpful factoid and much more can be found in TIFO's The Wise Book of Whys, which sounds like super bathroom reading.