Textbook in PDF format This book offers a comprehensive exploration of the history and development of power reactors worldwide, from their inception to the present day. It provides an in-depth analysis of light water reactors and their global technology, while also delving into the evolution of gas-cooled, heavy water, liquid metal-cooled, aerospace, and nuclear fusion reactors. By examining past advancements, this book equips readers with the insights necessary to apply lessons learned to future reactor development and utilization. Key concepts include the dominance of light water reactors in the global market, the progression of nuclear fuel cycle technologies, and the economic and political aspects of plutonium utilization. The book also addresses critical questions such as the potential depletion of uranium resources and the characteristics of Generation III and IV reactors. With contributions from government agencies and international organizations, this work is a must-read for those seeking a thorough understanding of nuclear reactor history and future challenges