Permanent magnets are materials which retain their magnetic properties permanently. In other words, they exhibit magnetic properties even if they are removed from a magnetic field. Permanent magnets can be broadly classified into rare earth, ferrite, aluminum-nickel-cobalt (Alnico), and other magnets. The rare earth magnets can be further subdivided into neodymium-iron-boron (NdFeB) and samarium-cobalt (SmCo) magnets. Permanent magnets are used in a wide range of applications including household equipment, electronic and medical devices, power generation devices, and automobiles.