Question

what is trackball??

Answer 1

A trackball is a pointing device consisting of a ball held by a socket containing sensors to detect a rotation of the ball about two axes—like an upside-down mouse with an exposed protruding ball. ... The trackball's buttons may be situated to that of a mouse or to a unique style that suits the user.

Answer 2

A trackball is essentially an inverted mouse where the user moves the ball. Unlike a mouse it stays stationary on the desktop and is generally attached or built in to the keyboard. The operations of a trackball are similar to mouse. Since it is a static device, instead of rolling the mouse on the top of the table, the ball on the top is moved by using fingers thumbs and palms.
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