This book explores cryogenic computers to achieve faster operation and lower energy use. As computer components become smaller and generate more heat, traditional cooling methods struggle to keep up. By operating at cryogenic temperatures, these limitations can be overcome-reducing heat, improving performance, and opening new possibilities for important applications such as large scale data centers and quantum computers. The approaches and physical models discussed in this book are valuable since these concepts offer a practical methodology for increasing computational computing power without being limited by heat and power dissipation. The book explores how cryogenic temperatures can supercharge computing. Novel methods for designing and optimizing computer systems that operate at extremely low temperatures, improve performance, reduce power consumption, and tackle the fundamental physical limits faced by modern electronics are introduced in this book. From foundational physics-based principles and cryogenic equipment to innovative graph theoretic design, the book offers a fresh look at the future of high performance, energy efficient computing. Provides a solid foundation in cryogenic computing and how it relates to traditional room temperature electronic design Describes a step-by-step framework for optimizing power, performance, and thermal loads in multi-temperature systems Includes novel solutions to some of the toughest challenges of computing, such as heat density and quantum effects.