From the back of the book: "Technical Introduction to the Apple IIGS is the first in a suite of technical books that will cover all aspects of the Apple IIGS personal computer, the newest and most powerful member of the Apple II family. Written for programmers and designers who want to develop for-or conver to- this new computer, Technical Introducation to the Apple IIGS is the starting poing for learning to make full use of its extensive capabilites."