Textbook in PDF format With the development of the modern information industry, space microwave technology, new materials, devices, and high-precision processing methods, secondary electron emission and its applications face new scientific and engineering challenges and opportunities. This book discusses theoretical models, measurements, data results, surface processes, and dielectric charging analysis of secondary electron emission. It covers key areas such as particle physics theory, simulation algorithms, magneto-hydrodynamics, surface processes, and surface characterization. The secondary electron yield and energy spectrum data are disclosed and analyzed, benefiting fields such as space microwave multipactor, scanning electron microscope (SEM), particle accelerator, and microwave plasma. Several typical application scenarios are also presented. Using the secondary electron emission data provided, this book shows how the secondary electron multiplication effect can be suppressed and exploited to improve device performance