What is the difference between a taser and a stun gun?

A taser is shaped like a gun, but has electrical probes that shoot out of the device, it’ll go through clothing and attaches to the attacker, vs. stun gun that has a button you press to provide an electrical charge when pressed against your attacker…they both cause pain to your attacker, but the taser disables your attacker, where the stun makes your attacker back off.