This article describes the main physical effects due to the propagation and guidance of electromagnetic waves in ferrite‐loaded waveguides useful in microwave technology. The linear approach, in which the high‐frequency magnetic susceptibility of the ferrite is a function susceptibility of the ferrite is a function static magnetic field, will be considered valid. This approach includes the analysis of exchange free electromagnetic waves, as well as magnetostatic waves approximations, but not the analysis of spin waves nonlinear effects, magnetoelastic waves, and other complex interactions.