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(a) What is a Scanner ? How does it work?
(b) Write down the purpose of: (i) Digital Video Camera, (ii) CD Writer

Scanner
It is a useful input device. Scanner reads data or information from source and then it converts every bit of the scanned material into electrical pulses. Suitable scanning software converts the printed documents, pictures into digital files. These digital files can be stored in computer’s memory.

Digital Video Camera
A camera that captures moving images and converts them into electronic signals so that they can be saved on a storage device, such as videotape or a hard drive, or viewed on a monitor.

CD Writer
A CD-writer is an output device. It can write once on a recordable compact disk (CD-R) to create a CD-ROM. The rapid and universal acceptance of compact disk read only memory (CD-ROM) has given rise to an exiting new technology.