Pointing devices enable us to be able to navigate around the graphical user interface of a computer system easily, without having to be aware of the various command line prompts that would otherwise be needed in order to open and utilise applications.
Similar to most computer system peripheral devices, pointing devices come in a variety of designs. The most common of these is the computer mouse, of which most of us will be familiar. Other pointing devices include game pads, touch pads, track balls, joysticks, and graphics tablets.
The ‘mouse’ gets it’s name from it’s original appearance; that of a small rounded rectangle with a cable attached to one end. A mouse sends data to the graphical user interface (GUI) by having it’s movement tracked across the desk or mouse pad.
Most of today’s mice make use of optical technology to detect it’s movement through use of a laser. Unlike it’s ball-type predecessors, the lack of mechanical moving parts makes this mouse both more accurate and reliable.
Today’s wired mice are generally connected to a computer system through a USB port and, similarly, wireless mice connect to the system through a USB port transceiver. Alternatively, some mice make use of Bluetooth wireless technology to achieve the same goal.
The most common of today’s mice mice that come bundled with computer packages will typically have two main buttons and a central ‘scroll wheel’. However, there are a number of variations on this with some mice having up to 24 buttons available. This variation in buttons can be used for such things as moving forwards and backwards within browser windows or may be used to program functions for higher level PC gaming. Other mice, such as those that come with Mac computers have only a single button present.
A Trackball Mouse is, to all intents and purposes, an upside-down version of a normal mouse. Instead of the later style of optical sensors, a trackball mouse has a ball just as the earlier versions of standard mouse had.
Signal are sent to a computer system from a trackball mouse by rolling it’s ball by movement of our fingers, thumbs or the palm of our hands. Similarly to a normal mouse, a trackball mouse will have at least one button to send signals to the computer system.
Touch Pad and Trackpoint
As the name might suggest a ‘touch pad’ is a small, touch-sensitive pad that is operated by the user running their finger across it’s surface. This is then converted into an electrical signal which is translated and transmitted to the system unit.
Most touch pads have buttons just like their mouse or trackball counterparts. However there are also a high number of them which can be configured to detect the user tapping it’s surface with their finger, thereby processing that information in the same way it would as a click of the associated button.
Similar to Touch Pads are Trackpoints. Trackpoints are normally found on laptops and are located either in the center or at the bottom of the system’s keyboard. Ordinarily, Trackpoints are a small joystick style button that respond to directional force from the user in order to move the mouse pointer around the screen.
other Pointing Devices
In addition to the more traditional pointing devices above, there are other devices that have another primary function, but can also be used effectively as pointing devices.
Gamepads are primarily designed to be used within gaming applications. They are typically held and manipulated with two hands and feature a number of buttons that control different actions within the game or program.
The latest versions of many game pads also have sensors or pointing devices that can sense rotation, as well as direction of movement. A combination of these two are used to control actions within the game or application.
Most typically, gamepads connect to a computer system through a USB port although the most recent consoles and PC gaming pads use various forms of wireless technology to connect to the system unit.
A joystick is a stick or lever which pivots around a base and is used to control movement on a device. The majority of current joysticks also include a number of additional controls, buttons, toggles or switches to control other associated actions that the input is controlling. The joystick itself inputs the angle and direction of any desired movement.
At one time, joysticks were the most common input device to be used with gaming programs and applications. However, with the introduction and improvements with gamepads, they are generally used more within flight or space simulators. In addition, joysticks are also often used to control machinery such as cranes and unmanned vehicles (drones).
Once upon a time, legacy joysticks were connected to computer systems via a ‘game port’, a device port that was designed specifically for connecting this style of input device. However, most modern joysticks employ a wired USB connection to connect to the computer system.