This document discusses input and output devices for computers. It describes input devices as the means for raw data to enter the computer, which are then processed by the CPU and outputs are produced. There are two types of input devices: manual devices like keyboards, mice, and touchscreens that require human interaction; and automatic devices like card readers, barcodes scanners, and sensors that input data without human involvement. Output devices communicate results to the user in formats like printed paper, sound, video, and on-screen displays. Examples of output devices include monitors, printers, plotters, speakers, motors and other actuators.