Monochrome Display is part of the category Display Hardware Supported.
The Atari ST could be connected to either a color monitor or t.v. or a monochrome monitor. Depending on the type of monitor used, different graphics modes were available to programs and games. With a color display, the Atari ST provided a graphics resolution of either 320x200 with 16 colors (out of 512) or 640x200 with 4 colors (out of 512); with a monochrome display, the only resolution available was 640x400 in 2 colors. Since each display type supported unique resolutions with no overlap, in order to work with both monitor types games would need to support compatible resolutions. It was, however, common for many Atari ST games to support color only. Games with this attribute support a graphics resolution compatible with a monochrome display
See also: Color Display