Pointing Devices are direct entry input devices. They allow users to control the pointer and the insertion point on the screen. Examples of pointing devices are mouse, trackball, touch pad, pointing stick, joystick, touch screen, light pen and graphics tablets.
A mouse is a computer device, which has a ball sealed at the bottom. It is attached with a cable to the system unit. When rolled on the flat surface, the movement of the ball will generate electrical circuits, which are then sent to the computer. The movement of the mouse controls the insertion point and pointer on the screen. Moving the mouse allows user to positions the pointer or cursor an indicator on the screen that shows where the next interaction with the computer will take place. When the mouse is moved to the left, the pointer will move to the left, when the users move it to the right, the pointer on the screen will move to the right. Many users turn to the mouse as a quick substitute for some functions of the keyboard. There are various types of mouse operations such as point, click, double-click, right click, drag and so on. A cordless mouse users infrared remote transmission to communicate with the computer. Normally there is an IrDA (Infrared Data Association) port on the system unit to receive the signals sent by cordless mouse.
A trackball is a pointing input device with a ball on the top. It is a type of upside-down mouse. The ball is manipulated by palm or finger. As with a mouse, movement of the ball causes electrical circuits, which are sent to the computer. The corresponding movement of the cursor on the screen. Trackballs are often built into laptop computers. Trackball can replace a mouse if the user cannot find a flat surface for an ordinary mouse to roll on. It is very useful to operate if there is a limited desk space.
A touch pad is a small sensitive area, normally built on the laptop computer. It is sensitive to pressure and motion. Once there is pressure or motion, signals will be generated in the electrical forms. It is another substitute for a mouse or trackball. Moving and tapping the fingers on the surface of a pad control the cursor.
A pointing stick is a pointing input device positioned between the keys on the keyboard. It was first found in IBM notebook computer. It is very small ad short which will be sent to the computer. A pointing stick is the substitute of a mouse or trackball. It does not require large desk space.
A joystick is a vertical level attached to a base. A user can move the stick in different directions such as left, right, front or back. Some joystick has buttons attached to it. Users can press the button to trigger certain events, or issue commands to the computers. Normally user uses it to run game software such as driving or flight simulator.
Touch screen is another type pointing device. It is a different kind of monitor screen covered with a pressure sensitive layer. Behind this layer are crisscrossed or commands by touching the screen with a finger. Touch screens are easy to use, and can be found in bank automatic teller machines (ATMs) and at visitor information centers in airport and hotels.
A light pen is a light-sensitive pen like device. User normally use light pen by pressing it against a specially designed monitor or just a standard monitor, then press the button on the pen in order to issue input commands to the computer. Light pens are normally covered with a protective sleeve. This prevents dirt, grease or other chemicals that could damage the computer. Instead of touching the screen with the finger to interact with the computer, user ogresses the light pen against the surface of the screen and then presses a button on the pen. Engineers, for example, use light pens in designing anything from microprocessor chips to airplane parts.
A graphic tablet, also known as a digitizer or digitizing tablet. It consists of a flat, rectangular, electronic plastic board used to input drawing, sketches or other graphical data. Each location on the graphic table represents a specific location on the screen. It is a device that can be used to trace or copy a drawing or photograph. Pens or cursors are normally used to perform drawing on the graphics tablets. The images are then converted into data that can be processed by the computer. Digitizers are often used by designers and architects.
The latest and future technologies of pointing devices are pointing devices and invented a wearable band which interprets muscle movement in to commands sent to Computers, Mobiles and or other controllable devices. The unit is on sale at the moment and looks promising and interesting and could be the reason of the extinction of the computer mouse. Besides that, they is a device call DUO device with its first real-world use as an advanced high resolution hand tracker. Demonstrating a brand new accurate and robust type of interaction with your computers, this shows that you can interact and control wide range of applications. The DUO, being a 3D sensor, adds an additional dimension and depth of control to the traditional 2D mouse input. Using natural hand and pen motion and gestures, you can control your computer in new unimaginable ways. The DUO comes bundled with powerful SDK/API allowing you to rapidly incorporate this new technology in your own projects regardless of the programming language you may use. The DUO is an envisioned as a DIY device allowing you to build your own and customize it in any way you choose. Without a doubt, the touch screen is also the future of the pointing device. As more technology is released using the touch screen, more users will become used to it. When that happens, the need for a mouse, roller ball or any other type of pointing device will slowly but surely become obsolete.