Calvin & Hobbes

Calvin: Dad, how come old photographs are always black and white? Didn't they have color film back then?

Dad: Sure they did. In fact, those old photographs are in color. It's just the world was black and white then.

Calvin: Really?

Dad: Yep. The world didn't turn color until sometime in the 1930s, and it was pretty grainy color for a while, too.

Calvin: But then why are old PAINTINGS in color?! If the world was black and white, wouldn't artists have painted it that way?

Dad: Not necessarily. A lot of great artists were insane.