Track Ball:
Trackball, a pointer device, is a mouse lying on its back(as show in given figure). To move the pointer, you rotate the ball with your thumb, your fingers, or the palm of your hand. There are usually one to three buttons next to the ball, which you use just like mouse buttons.
The Advantage of trackballs over mouse is that the trackball is stationary so it does not require much space to use it. In addition , you can place a trackball in any type of surface, including your lap. For both these reasons, trackball are popular pointing devices for portable computers.
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| Fig. Track Ball |
While the standard mouse has replaced the trackball for the majority of home computer users, a lot of specialized work environments still use trackballs due to their precision. Trackballs are used in a variety of fields, from air-traffic controlling to operating equipment to drafting and design work.
