The Color Graphics Adapter (CGA), originally also called the Color/Graphics Adapter or IBM Color/Graphics Monitor Adapter, introduced in 1981, was IBM's first color graphics card for the IBM PC and established a de facto computer display standard.

The original IBM CGA graphics card was built around the Motorola 6845 display controller, came with 16 kilobytes of video memory built in, and featured several graphics and text modes. The highest display resolution of any mode was 640 × 200, and the highest color depth supported was 4-bit (16 colors).

The CGA card could be connected either to a direct-drive CRT monitor using a 4-bit digital (TTL) RGBI interface, such as the IBM 5153 color display, or to an NTSC-compatible television or composite video monitor via an RCA connector. The RCA connector provided only baseband video, so to connect the CGA card to a television set without a composite video input required a separate RF modulator.

IBM produced the 5153 Personal Computer Color Display for use with the CGA, but this was not available at release and would not be released until March 1983.

Although IBM's own color display was not available, customers could either use the composite output (with an RF modulator if needed), or the direct-drive output with available third-party monitors that supported the RGBI format and scan rate. Some third-party displays lacked the intensity input, reducing the number of available colors to eight, and many also lacked IBM's unique circuitry which rendered the dark-yellow color as brown, so any software that used brown would be displayed incorrectly.

CGA offered several video modes.

Graphics modes:

Some software achieved greater color depth by utilizing artifact color when connected to a composite monitor.