Book excerpt: Hemodynamics is the study of dynamics in the circulatory system. Hemodynamics has been essential in clinical practice pertaining to cardiovascular diseases from ancient days. Although it is essential because it is based on dynamics and physics, the understanding of hemodynamics is hard for all those concerned with cardiovascular diseases. In addition, with the rapid progress of recent imaging and computer technology, hemodynamics research has undergone an evolution that provides beautiful, colorful blood flow visualization. This kind of innovation contributes novel insights into the approach to the pathophysiology of cardiovascular diseases. This textbook includes the comprehensive knowledge regarding hemodynamic research from basic physiology to recent clinical problems. This textbook has two parts: the first includes the basics of hemodynamics research and the second presents its clinical applications. This textbook covers all the current topics and all the important historical topics related to hemodynamics. In this edition, each chapter was written by professional authors regarding their respective topics. Careful attention was paid to make it appeal to a wide range of professionals including clinicians, engineers, physicians, and researchers. Each chapter is independent of the others, and this textbook was written both to be read through and to be used as a reference for any special topics. We hope this textbook will provide new perspectives to all those interested in the research regarding hemodynamics.