Peripheral devices: A peripheral device is any device that can be connected to a computer. This term includes monitors, keyboards, mouse, webcams, drawing pads, joystick, modems, printers, scanners, interactive whiteboards, drive wheel, and so on.Input devices: Any device that is capable of inputting information into a computer system, for example, keyboard, microphone, mouse, scanner, webcam, and so on are known as input devices.Output devices: The output devices are basically meant for anything that comes out of a computer after being processed. It includes the monitor, headphones, printers, speakers, projectors, plotters, and VDUs (visual display units).Storage devices: Computer data storage, often known as memory refers to the computer components and recording media which retain the digital data. Memory refers to the temporary internal storage areas within a computer. The term memory is usually used as a shorthand for physical memory and it refers to the actual chips capable of holding data. Some computers also use virtual memory, which expands physical memory onto a hard drive.Therefore, when we give input through scanners, trackballs, microphones, touch screens we can see/access those input data over the screen of the computer, hence these devices can be put under the category of input peripheral devices.