A ferromagnet is a material that can become magnetized and retain its magnetic properties even after an external magnetic field is removed. This occurs because the magnetic moments of atoms in ferromagnetic materials, such as iron, cobalt, and nickel, align in the same direction, creating a strong overall magnetic field. Ferromagnetic materials are commonly used in various applications, including permanent magnets, transformers, and electromagnets. Their ability to maintain magnetization makes them essential in technology, such as in electric motors and data storage devices.