Chapter 1 Introduction This chapter gives a brief description of the problems considered in this book and the key results presented in each chapter. 1.1 What is This book about? This book is about basic robust and Hoo control theory. We consider a control system with possibly multiple sources of uncertainties, noises, and disturbances as shown in disturbanc other controlled signals System Interconnection controlle reference signals Figure 1.1: General system interconnectionChapter 1 Introduction This chapter gives a brief description of the problems considered in this book and the key results presented in each chapter. 1.1 What Is This Book About? This book is about basic robust and H∞ control theory. We consider a control system with possibly multiple sources of uncertainties, noises, and disturbances as shown in Figure 1.1. controller reference signals tracking errors noise uncertainty uncertainty other controlled signals uncertainty disturbance System Interconnection Figure 1.1: General system interconnection 1