Input and Output Devices Essay

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3.0 Introduction Input devices accept user commands or data and send them to the computer for processing. Typical input devices are keyboard, mouse, scanner and microphone. On the other hand, output devices accept results or information generated by the computer, and present this to the user in a variety of means (both audio and visual e.g. textual, image, video). Typical output devices are printers, monitors and speakers. Some special devices can be used for both input and output, such as floppy disks and hard drives. Computer input and output devices have undergone remarkable development with advances in technology. 3.1 Input devices With all the input devices available today, users may find it difficult to determine which one is best for entering data into their personal computer. The main function of input devices is to convert people-readable form of data into a machine-readable form that the computer can store and process. People readable form of data can be letters, numbers, visual codes and symbols. Machine-readable forms of data consist of electronic signals of 0's and 1's. A personal computer is normally equipped with a mouse and keyboard as standard input devices. Input devices can fall under three categories, namely pointing, scanning and voice. Input can be made by keyboard or direct entry. 3.1.1 Keyboard Most modern computer keyboards are based on the QWERTY layout, and resemble a typewriter keyboard except that they have extra keys for certain special functions, such as: Function keys: located at the top of the keyboard with prefix F, example F1, F2 and so on. However, these shortcuts on depends on the specific software used. Numeric keypad: located on the right corner of the keyboard, is a separate set of number keys, like that of a calculator, for quick input of numbers and arithmetic operators. Arrow keys or navigation keys: located between
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