The IBM PCjr and Tandy 1000 computers included a native graphics mode of
160x200 with 16 colors not found on most other IBM or compatible systems. Most games
supported either the more common 320x200 16 color or 320x200 4 color modes, however a few games
utilized the 160x200 graphics for at least some screens (or more commonly for the entire game)
in order to either use less memory, make the graphics easier to port from other systems such as the Commodore 64, or to improve performance on slower systems.
See also: Tandy/PCjr Graphics.