trackball

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trackball

[′trak‚bȯl]
(computer science)
A ball inset in the console of a video display terminal, which can be rotated by the operator, and whose motion is followed by a cursor on the display screen.

trackball

A stationary pointing device that contains a movable ball rotated with the fingers or palm. From one to four keys are located in various positions depending on the unit. In the late 1980s and 1990s, Kensington Microware popularized the trackball with its Turbo Mouse for the Macintosh. Turbo Mouse for Windows was subsequently released, and over the years, the Turbo Mouse evolved into the Expert Mouse and Orbit brands.

The advantage of the trackball, and the reason many people like it, is that the unit remains in the same position on the desk, and only the ball is moved. See mouse, pointing stick and touchpad.


The Turbo Mouse
The Turbo Mouse popularized the trackball for the Macintosh. Later models were developed for the PC. (Image courtesy of Kensington Microware, Ltd.)
References in periodicals archive ?
The new six-way control ball valves from Siemens have a built-in pressure compensation function which is active when the valve is in the closed position (ie when no heating or cooling is needed).
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offers a color brochure dedicated to its CAGE-BALL high-performance control ball valve.
The "Suministro de Gas Combustible al Centro Operativo San Joaquin" natural gas pipeline project will be equipped with the Dresser Becker QTCV-T2 and QTCV-T4 quiet trim control valves, Dresser Becker RPSR rotary piston spring return actuator, Dresser Becker VRP-SB-PID valve regulator pilot, Dresser Masoneilan SVI([R]) II AP digital valve positioners, and Dresser Masoneilan V-Max control ball valve.