- Published: August 28, 2022
- Updated: August 28, 2022
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Input and Output Devices Roll No: Teacher: 31st May 2009 Input and Output Devices Computer system is an electronic device that processes data according to a set of stored instructions. The system receives input data, carries out some process on it and then outputs the data in form of information. For input to the computer system, input devices are used and for data output, output devices are employed. Computer works by means of input and output devices.
A computer system can do very little useful work without some form of input device. These take information from the outside world, transform it into data that the computer system can manipulate and provide it to the CPU (Central Processing Unit). The most common form of input devices are intended for use by humans, but there are many other types of input devices, which communicate with other systems, not people.
In addition to input devices, we also require output devices, which can present the data that the computer system is manipulating in the form of useful information. Like input devices, there are many forms of output devices presenting information in the form of graphics, printed paper, sound, movement and signals that other computer systems can utilize.
Some devices are used both for input and output. This is particularly true when we are considering the means by which one computer system can be linked with the other. Both input and output devices are often called peripherals. This is because they are usually attached to the outside (the periphery) of the unit that houses the CPU and the memory.
KeyboardMousePrinter
Keyboard can be considered as the chief input device for the computer system, which is basically the same as the mechanical typewriter keyboard as it has keys for printing upper and lower case letters, numbers and a variety of symbols. However, since it is used to input more than just letters and numbers, it needs to have extra keys to perform additional actions. Like keyboard, mouse is also an input device. It provides positional information to the computer.
Digitizing or graphic tablets are input devices found on computer aided Design (CAD) systems, engineering workstations and other specialized systems. The tablets contain a tablet, a digitizing pen and a controller. Scanners are used to copy images from hard copy to the computer and they are also input devices. Microphone is used to input voice to the computer system while video camera is used to input pictures and videos to the computer system.
Printers are primary output devices used to prepare permanent documents for human use. There are many kinds of printers for printing data such as dot matrix, line printers, laser printers, ink jet printers. Graphic plotters are also output devices that use pens or ink jets to produce images on paper or film. The distinguishing feature of plotters is that they can produce much larger images than other kind of printers. Monitor is also a major output device as it displays the functioning of data in form of information on the screen.
References
Input and Output Devices. Accessed on 31st May 2009 from http://www. free-computer-tips. info/tutorials/computer-hardware/input-and-output-devices. html