A component or peripheral device (such as a barcode reader, graphic tablet, keyboard, magnetic-stripe reader, modem, mouse, scanner, or stylus) that feeds data or instruction into a computer for display, processing, storage, or outputting or transmission.Input devices convert the user's actions and analog data (sound, graphics, pictures) into digital electronic signals that can be processed by a computer. Digital data (such as from barcode readers, modems, scanners, etc.) does not require any conversion and is input direct into a computer. It is through input devices that a user exercises control over a computer, its operations, and outputs.
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