The AS/400 is IBM’s newest midrange processor. This thoroughly readable text consists of four parts: “Introduction and Concepts,” “Development Tools,” “Languages,” and “Integrations, Communications, and Migration.” It describes how the AS/400 works and what it can do. It is obviously not intended to be a complete reference on the AS/400, but rather is a compilation of the material needed to understand the architecture of the AS/400 and to begin working effectively with the system.

In addition to covering the AS/400, the book sheds light on IBM’s Systems Application Architecture (SAA) by describing the midrange computing architecture that IBM envisions to interconnect its mainframe and personal computing technologies. AS/400 is a key component in IBM’s view of true distributed processing among micros, minis, and mainframe computers, in which the various platforms are connected using networks to share data and software in a fully compatible computing and networking infrastructure.

This book is an excellent introductory text, especially for systems professionals who understand the structure and use of computers and applications and basically need an update on the AS/400 technology, which is rapidly evolving into the standard for midrange computing. It is therefore a must read for all serious information systems professionals, regardless of their technological specialty or background.