A tuning fork produces a pure tone, which is a sound wave with a single frequency. The button on a tone dialer, on the other hand, produces a more complex sound wave that contains multiple frequencies. This is because the button on a tone dialer is struck by a hammer, which causes the metal tines of the fork to vibrate. These vibrations create sound waves that travel through the air and reach our ears. The sound waves produced by a tuning fork are much simpler than those produced by the button on a tone dialer, because they only contain a single frequency.