What are output devices of computer and define each output device and what are functions of each output device

Define computer output devices and its types?

An output device is any electronic or electro mechanical equipment connected to a computer and used to transfer data out of the computer in the form of text, images, sounds or other media. Examples of output devices include monitor, printer, plotter, and speaker. It is used to give information and present results to the user.
a. Monitor: the monitor show information on the screen menu type. This is called out putting information. Most desktop computer uses a monitor with a cathode ray tube (CRT) or liquid crystal display (LCD).
b. Printer: a printer is an output device that produces a hard copy of data. The resolution of printer output us expressed as DPI. Printer is used to print the output data on the paper.
c. Plotter: A plotter is a special purpose output device that draws images with ink pens. That is, the plotter is a graphic printer for making sophisticated graphics, charts, maps and three dimensional documents as well as high quality colored documents.
d. Voice output device: this device produces a human speech like sound, but actually is pre recorded, vocalized sounds. Voice output is used in the telephonic information system where the requested number is reported using a voice output system.

What is processing unit?

Processing unit is commonly called center processing unit. It is the brain of the compute. It comprises the arithmetic logical unit and control unit. It performs operation on the input data.

Input device digital camera: 

                                                It allows taking digital photograph; the images are stored in a memory chip or disk that can be transferred to the computer. Some computer can also capture sound and video.