A magician I know talks about the three kinds of magic: sleight of hand, mechanical, and mathematical. The first requires a lot of skill and practice (e.g., palming coins, manipulating cards). The second requires a lot of preparation and engineering (e.g., sawing a person in half, floating person illusions). The third relies on the nature of reality (e.g., dividing sets of cards in a known pattern that forces a result, or manipulating numbers that force an unexpected result).
So this is a cool example of the second type. All three types require some showmanship, and good patter. Some of the best tricks combine the types.