The monitor is a passive device that just displays the video output from the system. However, so much data is needed for the constantly changing screen display that special provisions are made for it.
The video card (or video circuitry on the motherboard) has its own RAM memory just to hold the display information, and its own ROM BIOS to control the output. Some motherboards even have a special high-speed connection between the CPU and the video. It’s called the AGP, or Accelerated Graphics Port.
The important numbers in evaluating a video display are how many distinct colors can be displayed and also the resolution, which is how many pixels the image contains across and from top to bottom. Each dot of color making up the image is one pixel. As video technology evolved there have been a number of standards, and each one has its own set of initials like EGA, CGA or VGA. A common one isSVGA, which stands for SuperVideo Graphics Array and has a resolution of 800x600 (that’s 800 pixels across and 600 down). Some high-performance monitors use SXGA (1280x1024) or even UXGA with a resolution of 1600x1200.
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