A discussion of the basic concepts of magnetism, including magnetic fields, magnetic poles, and electromagnets. I also discuss the ultimate subatomic source of magnetic force in the phenomenon of electric spin, and explain how this leads to the different types of magnetic materials: ferromagnets, paramagnets, and diamagnets. I conclude with some applications of electromagnetism, including electric generators and motors, transformers, and a brief discussion of Maxwell's equations. Recommended prelistening is Episode 43: Electric Forces and Fields.