Pointing device
Graphical user interfaces (GUI) and CAD systems 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.
An indirect-input pointing device is not at the same physical position as the pointer but translates its movement onto the screen (e.g., computer mouse, joystick, stylus on a graphics tablet).
A position-control input device (e.g., mouse, finger on touch screen) directly changes the absolute or relative position of the on-screen pointer.
A rate-control input device (e.g., trackpoint, joystick) changes the speed and direction of the movement of the on-screen pointer.
Examples The following table shows a classification of pointing devices by their number of dimensions (columns) and which property is sensed (rows) introduced by Bill Buxton.
Even if these movements take place in two different spaces, the units for measurement have to be the same in order to be meaningful (e.g. meters instead of pixels).
[6] The Microsoft, macOS and X window systems have implemented mechanisms which adapt the CD gain to the user's needs.
This device is very similar to the conventional mouse but uses visible or infrared light instead of a roller-ball to detect the changes in position.
[8] Additionally there is the mini-mouse, which is a small egg-sized mouse for use with laptop computers; usually small enough for use on a free area of the laptop body itself, it is typically optical, includes a retractable cord and uses a USB port to save battery life.
Tracker balls are commonly used on CAD workstations for ease of use, where there may be no desk space on which to use a mouse.
A main feature of the Wii Remote is its motion sensing capability, which allows the user to interact with and manipulate items on screen via gesture recognition and pointing through the use of accelerometer and optical sensor technology.
The thumb usually controls the clicking via a two-way button on the top of the pen, or by tapping on the tablet's surface.
A cursor (also called a puck) is similar to a mouse, except that it has a window with cross hairs for pinpoint placement, and it can have as many as 16 buttons.
A stylus is a small pen-shaped instrument that is used to input commands to a computer screen, mobile device or graphics tablet.
At least one physical button normally comes with the touchpad, but the user can also generate a mouse click by tapping on the pad.
Advanced features include pressure sensitivity and special gestures such as scrolling by moving one's finger along an edge.
Users interact with the device by physically pressing items shown on the screen, either with their fingers or some helping tool.
Resistive and capacitive touchscreens have conductive materials embedded in the glass and detect the position of the touch by measuring changes in electric current.
Modern touchscreens could be used in conjunction with stylus pointing devices, while those powered by infrared do not require physical touch, but just recognize the movement of hand and fingers in some minimum range distance from the real screen.
Touchscreens became popular with the introduction of palmtop computers like those sold by the Palm, Inc. hardware manufacturer, some high range classes of laptop computers, mobile smartphone like HTC or the Apple iPhone, and the availability of standard touchscreen device drivers into the Symbian, Palm OS, Mac OS X, and Microsoft Windows operating systems.
