A pointing device is an input interface that allows a user to input spatial (i.e., continuous and multi-dimensional) data to a computer. CAD systems and graphical user interfaces (GUI) allow the user to control and provide data to the computer using physical gestures by moving a hand-held mouse or similar device across the surface of the physical desktop and activating switches on the mouse. Movements of the pointing device are echoed on the screen by movements of the pointer (or cursor) and other visual changes. Common gestures are point and click and drag and drop.
Initially, interaction with computers was restricted mainly to text mode. However, users and computer designers soon realized that text-mode interaction is cumbersome, time-consuming, and limited in scope operation. Hence, computer designers came out with the idea of a new type of user interface, called graphical user interface (GUI). A GUI provides a screen with graphic icons (small images on the screen) or menus and allows a user to make rapid selections from them to give instructions to a computer. For efficient utilization, GUI requires an input device with which a user can rapidly point and select a graphic icon or menu item from multiple options displayed on the screen. The keyboard, though usable, is inconvenient and unsuitable for this requirement gave birth to several input devices like mouse, track ball, joystick, light pen, and touch screen. Later designers realized that many of these devices, like mouse and light pen, are also useful for effectively creating graphic elements on the screen such as lines, curves, and freehand shapes . With this new ability , manufacturers and users of these devices started calling them point-and-draw devices. They have made computers a more easily usable tool, establishing them as a versatile tool for a wide range of users including children, illiterate citizens, and graphic designers. Some commonly used point-and-draw devices are described below.
The point and draw device is an input system that helps to point and select an icon to be shown on the screen quickly. Some of the most common point and draw devices are. Trackball, Mouse, Joystick,