For the past 100 years physicists have debated the nature of the momentum of light inside material media. Hermann Minkowski, for example, asserts that within a transparent dielectric the momentum of a photon is the photon's vacuum momentum multiplied by the refractive index of the dielectric. An opposing theory postulated by Max Abraham, contends that the vacuum momentum must instead be divided by the refractive index. There have also been questions about the electromagnetic momentum inside magnetic media, and whether or not a part of the momentum is hidden. This book explains the laws of classical electrodynamics concisely and clearly, before elaborating on how to calculate force, torque, momentum and angular momentum using the exact forms of the laws, without any approximations. The author subsequently demonstrates what happens to the momentum of light when it enters various media (e.g., dielectric, magnetic, wholly or partially transparent, etc.). Thus the book provides a clear picture of the momentum of the electromagnetic field, resolves the Abraham-Minkowski controversy, and shows that there is no need for resorting to hidden momentum or any other exotic, unphysical concept. Numerical simulations are used along the way and throughout the chapters to elucidate the propagation of energy, momentum, and angular momentum under circumstances which are too complicated to solve analytically. This book is a useful resource for students and academics interested in quantum optics.