Video Display Unit (VDU) or Monitor
Video Display Unit is similar to a television. It is used to display the results of processes. The screen is illuminated by a number of dots known as pixels. The number of dots per unit area is called resolution. The higher the resolution, the better will be the quality of the picture. A lighted symbol in a form of a line or rectangle visible on the screen known as Cursor, to indicate the position for typing a command. If any keys are pressed, it moves along the alphabet typed. A typical Video Display Unit screen can accommodate 25 lines, each line consisting of 80 characters.
There are various kinds of printers. They are basically divided into two categories:
Impact printers and Non-impact printers.