An electromagnet is a type of magnet in which electric current produces a magnetic field. The electromagnets are used in electrical devices such as motors, generators, electrochemical solenoids, relays, and MRI machines. A solenoid is an electromechanical device that generates a mechanical motion when electric current is passed through it. The principle of solenoid is used in a device called as a relay to open and close light-current electrical circuits. Electromagnetic materials have a wide range of applications. They are used in various fields such as communications, research, and magnetic recording. Modern telephone systems are based on the reed relay along with solid-state circuits for complex routing of connections. This book outlines studies that have been carried out with respect to the properties and applications of electromagnetic materials. It will provide comprehensive knowledge to the readers.