An input device for a computer is described that positions the user's hand in a more ergonomically desirable position, i.e., at an angle of about 45° to the work surface. In preferred embodiments, the input device accommodates either a user's left or right hand, and in either case, positions the hand in an ergonomically desirable position. In another embodiment, the length of the input device of the present invention is adjusted for the size of the user's hand. In further embodiments, the input device of the present invention provides a palm rest. Other desirable features included in preferred embodiments include lateral buttons that are positioned one above the other.