Specifies a set of functions for computer graphics programming, the Graphical Kernel System (GKS). GKS is a basic graphics system for applications that produce computer generated two-dimensional pictures on line graphics or raster graphics output devices. It supports operator input and interaction by supplying basic functions for graphical input and picture segmentation and allows storage and dynamic modification of pictures. The application program is allowed to adapt its behaviour at a workstation to make best use of workstation capabilities. This Standard includes functions for storage on and retrieval from an external graphics file, the functions being organized in upward compatible levels with increasing capabilities. Identical with ISO 7942.