tracker ball


tracker ball

(hardware)A pointing device consisting of a ball housed ina socket containing sensors to detect rotation of the ballabout two axes - like an upside-down mouse. The user rollsthe ball with his thumb or the palm of his hand to move acursor. Tracker balls are common on CAD workstations forease of use and on modern portable computers, where theremay be no desk space on which to use a mouse. Some cliponto the side of the keyboard and have integral buttons whichhave the same function as mouse buttons.