Input, Output, and Internal Peripherals
A computer accessory, or peripheral, is an input or output device that is connected to a computer, but it is not essential to the functioning of the computer. That is, peripherals expand the computer's capabilities but are not part of the core computer architecture. Generally speaking, peripherals are used to describe devices that are external to the central processing unit of a computer. Technically speaking, however, devices located within the central processing unit are also peripherals, such as CD/DVD ROM drives or internal hard drives, but they are considered integrated peripherals. Sometimes peripherals are dependent on the computer to function, but not always. Input peripherals are used to interact with the computer, such as mice, keyboards, webcams, and microphones. Output peripherals are accessories which provide output to the computer user, including monitors, printers, and scanners.
A computer mouse is a peripheral or input device, used as a pointing device to navigate the screen. The motion translates into the motion of a pointer on a computer display or screen, allowing for control of a graphical user interface (GUI). A computer keyboard is a typewriter-like device with a number of keys that allow the user to input letters, numbers, symbols, and commands to a computer or similar device. A webcam is a video camera connected to a computer which allows users to see real-time images of themselves or whatever is in the view of the webcam on the computer screen.
A computer monitor is the most used output device of a computer. It is an electronic display, displaying instant feedback of video and graphics generated by the video card of the computer. They are actually very similar to televisions, but monitors typically have much higher resolutions. A printer accepts a text and/or graphic output from a computer and transfers that output to paper. In other words, a printer represents an electronic document on physical media. In computing, a scanner is a device that converts images, text, or objects into digital images. It does this by optically scanning the image into a digital representation which can be viewed on a computer.
A hard drive is an internal peripheral of a computer. A hard drive, also known as a hard disk drive, is a storage device used for storing and retrieving data or digital information in a computer. CD/DVD-ROM drives are internal peripherals that read audio, video, or other data from CD and DVD storage disks. Random access memory (RAM) is also an internal peripheral. It allows for data to be stored and accessed directly in a random order. This is in contrast to a hard disk or CD, where data is read in only a predetermined order.