Automobiles are designed to provide safe and comfortable movement to people all over the world. In order to accomplish this mission, car makers have focused on functional development including safety performance, environmental performance, driving performance, and provision of comfortable space. A wide variety of material technologies related to magnetic circuits are applied in the automobiles. These technologies have supported the development of the automobile industry and have become indispensable for high functionality and performance of the automobiles. This section will describe the relation between the basic functions of automobiles, namely, “run,” “turn,” and “stop,” discuss the application of magnetism from the historical point of view, and explain the latest technologies and future prospects.