The monitor or Visual Display Unit (VDU) is the standard output device of a computer system. The monitor is used to display the output of the operating system and the application packages used with the system. This output in modern systems will be high resolution colour.
In order to perform its function a monitor must receive mains power and it must be correctly connected to the motherboard. This connection is achieved by special hardware known as a graphics card also known as a video card.
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