trackballs

Trackballs are pointing devices that feature a ball housed in a socket. The ball remains stationary while the user rotates it with the fingers, thumb, or the palm. The ball’s movement is detected by sensors and translated into cursor movement on a computer display, typically along the x and y axes. Modern trackballs often allow adjustable sensitivity and acceleration.

Compared with a traditional mouse, a trackball generally requires less arm movement and can be used in tighter spaces or on uneven surfaces. This makes it appealing for long work sessions, ergonomic applications, or environments where desk space is limited. Trackballs are commonly used in CAD, GIS, and other professional settings, and they come in various form factors from small thumb-operated units to larger full-hand designs.

Internally, trackballs may rely on mechanical sensors with rollers that contact the ball to detect rotation, or on optical or capacitive sensors that track the ball’s movement more directly. Many models also include additional input buttons and, in some cases, a scroll ring around the ball for navigation.

Maintenance involves occasional cleaning of the ball, the socket, and the sensors, since dust and fibers can affect tracking. Compatibility and driver support can vary, but most major operating systems provide generic support for trackballs.

Notable examples include models from Kensington, such as the Expert Mouse, and Logitech’s TrackMan line, along with various other brands offering thumb- or palm-operated variants. Trackballs remain in use for specialized professional tasks and as niche consumer peripherals, valued for their space efficiency and potential ergonomic benefits.