Ferromagnetic materials exhibit magnetic behaviour similar to ferromagnetism below a critical temperature, known as curie temperatures. Above which it turns out to be paramagnetic. The origin of ferrimagnetisms is based on magnetic ordering. All atoms have their spins aligned in one direction and all other atoms have their spins aligned in the opposite directions. The oppositely directed magnetic moments have different magnitude and do not cancel. The net effect is that the crystal can possess magnetization even in the absence of an applied field. All useful magnetic materials in electrical engineering are either ferromagnetic or ferrimagnetic.