The video card is the component inside the computer that relays data to the monitor from the CPU. The differences between video cards come in the video card's efficiency in relaying this data. The way a monitor works is that it displays pictures a certain number of times per second. Thus, the video card sends information to the monitor that number of times per second. This is called refresh rate.
The video card also needs to handle certain resolutions with different amounts of colors. All of this requires memory, which usually needs to be on the card itself. The monitor, also needs to support the refresh rate, resolution and color depth that the card is working at. AGP cards are especially quick and can support very large resolutions, since AGP allows for extremely fast transfers between the CPU and the video card. This also allows for faster transfers between the video card and the monitor since the video card receives information at a faster speed. Some advanced video cards also have built in functions to work with 3D graphics, and render 3D worlds to the screen.
[an error occurred while processing this directive]