"This textbook is a graduate-level introduction to cosmology and particle astrophysics, which will also serve as a useful reference for researchers working in and across these areas. The book covers cosmology, as well as a variety of other topics in high-energy/particle astrophysics, such as cosmic-ray acceleration, neutrino astrophysics, gamma-ray astrophysics, and gravitational waves. In addition, it discusses many modern topics, including dark matter candidates and searches, the cosmic microwave background, and high-energy/multi-messenger astrophysics. It should serve graduate-level courses in particle astrophysics, high-energy astrophysics, or cosmology (particularly, the early universe). Problems are featured as an essential part of each chapter"--