Since 1960, the study of turbulence has been enhanced by developments in areas such as laser anemometry, powerful computers, digital data processing, and theoretical methods from quantum physics. Turbulence is the archetypal, non-linear, non-equilibrium problem of statistical physics; the fundamental problems of turbulence are still unsolved, but there is growing interest in their solution. This book aims to look at fluid turbulence from the point of view of engineering science and physics to produce an integrated treatise on the nature of the physics of fluid turbulence as a universal phenomenon with a universal behaviour. As these topics are almost exclusively theoretical, the closing chapters of the book may be seen as attempting to restore a balance by dealing with some of the more practical aspects of the subject, while at the same time illustrating the amazing diversity of physical phenomena which has emerged from experimental studies of turbulence over the last few years. It is designed for those who are new to the subject and also for those familiar with the more traditional branches of the study of turbulence but not with the usages of quantum physics.