A video adapter is a board that plugs into a personal computer to give it display capabilities. The display capabilities of a computer, however, depend on both the logical circuitry (provided in the video adapter) and the display monitor. A monochrome monitor, for example, cannot display colors no matter how powerful the video adapter.
Many different types of video adapters are available for PCs. Most conform to one of the video standards defined by IBM or VESA.
Each adapter offers several different video modes. The two basic categories of video modes are text and graphics. In text mode, a monitor can display only ASCII characters. In graphics mode, a monitor can display any bit-mapped image. Within the text and graphics modes, some monitors also offer a choice of resolutions. At lower resolutions a monitor can display more colors.
Modern video adapters contain memory, so that the computer’s RAM is not used for storing displays. In addition, most adapters have their own graphics coprocessor for performing graphics calculations. These adapters are often called graphics accelerators.
Video adapters are also called video cards, video boards, video display boards, graphics cards and graphics adapters.
Also see Understanding Video and Graphics Adapters in Webopedia’s “Did You Know…?” section.