A cat video about the science of cats
Two things I learned from this video:
1: I am my cat's Facebook page. That rubbing-up-against-you-and-leaving-scent thing? It's not just to mark you as "theirs". It's also a way of communicating information about themselves to other cats that you might encounter.
2: My cats poop in a box and bury it as a gesture of submissiveness to me. Good cats.