A slab of plastic with a picture on that moves. Massively influential on people's behaviour and society.
They're everywhere, the buggers. Nobody knows what they are for or why there are so many.
There is nothing else that looks like cakes, except other cakes. Cakes are an entirely man-made object, yet nobody seems to wonder why cakes look like cakes. Who decided what a cake should look like and why. Just so odd.