This book is an exploration of interaction between humans, computers and automated machines and why they frequently go awry, sometimes with disastrous consequences. The book lays out a clear foundation for evaluating interactions between users and machines, showing the reader how to describe, analyze and quickly identify potential design problems. The insights and methodologies provided allow the reader to understand the root human-interaction problems in modern systems, improve the usability of new user interfaces, and, the author hopes, have a say in the design of the highly automated systems of the future.