The Atari Trak-Ball is a trackball controller compatible with several Atari systems, including the 2600. It features two action buttons and a ball that can be spun in any direction for directional input. Games like Missile Command and Centipede used a trackball in their original arcade versions, giving arcade purists a strong incentive to use the Trak-Ball controller. Unfortunately, the Trak-Ball was not well supported and very few games actually used it in trackball mode. Trackballs offer more precise control than digital joysticks, but in modern controllers trackballs have been abandoned in favor of analog sticks.