Thermal radiation studies have progressed rapidly, not only in theoretical and experimental exploration beyond the conventional use but also in advanced applications. This is a one-stop resource for capturing and discussing these cutting-edge developments exploring the theory, experiments, and applications of thermal radiation from macro- to nanoscale. Presented in a systematic framework, this book is divided into two parts: the first on macroscopic thermal radiation and the second on micro- and nanoscale thermal radiation. Each part delivers basic theory, numerical methods, advanced experimental techniques, and promising applications, making this an easy-to-follow guide meeting both basic and advanced needs. Supported by more than 180 colorful illustrations, readers can clearly visualize the theory, experiments, and applications in practice. A book for all, written at a graduate level but undoubtedly a useful tool for researchers, professionals, and even engineers who are interested in this fast-developing area.