The Programmer's Hierarchical Interactive Graphics Standard (PHIGS) is a standardized description of the functional capabilities of a graphics system, upon which a variety of applications may be built. Attempting to combine a modeling system and a viewing system in a single standard, PHIGS contains a wealth of concepts to facilitate the development of interactive programs for the rapid definition, display and modification of 2D and 3D data. Introduces applications programmers to the key concepts by way of examples that will be extended as the book progresses. A large number of diagrams illustrate these examples.