Video cards

The quality of the image that a monitor can display is defined as much by the video cards also called the video controller or the video adapter as by the monitor itself. As show in figure 3A .19, the video controller is an intermediary device between the CPU and the monitor. It contains information to the monitor for display on the screen. In most computers the videos card is a separate device that is plugged into the motherboard. In many newer computers, the video circuitry is built directly into the motherboard, eliminating the need for a separate card.

In the early days of personal computing, PC screen displayed only text characters and usually only in one color. These displays took little processing power because there were only 256 possible characters and 2,000 text positions on the screen. Rendering each screen required only 4,000 bytes of data.To-days however; computers are required to display high-quality color graphics as well as full-motion animations and videos. These display took little processing power because there were only 256 possible characters  and 2000 text positions on the screen.