Hero of Alexandria was an innovator in the field of automata but that's not all. It is highly likely that Hero was the inventor of the first programmable robot. The robot had three wheels and carried a group of other automatons onto a stage to preform. The robot's movement was controlled by a string wrapped around an axial with a series of pegs. The pegs were used to reverse the direction of the string so that the cart could drive itself in different "pre-programmed" directions.