First, the magnets is a ferromagnetic substance. To make it magnetic it is necessary to magnetize it so that it will be demagnetized if it disappears (degaussing). Definition Magnetization refers to the process of obtaining a magnetism from a substance that is not originally magnetic. Principle Magnetic material is divided into many small areas, each tiny area called a magnetic domain, each magnetic domain has its own magnetic distance (that is, a tiny magnetic field). Under normal circumstances, each magnetic domain of the magnetic distance in different directions, the magnetic field offset each other, so the whole material is not significant external magnetic. When the direction of each magnetic domain tends to be consistent, the whole piece of material shows magnetism to the outside. The so-called strong magnet magnetization is to make the direction of the magnetic distance of the magnetic domains in the magnetic material become the same. When a nonmagnetic material is put into another strong magnetic field, it is magnetized. However, not all materials can be magnetized. Only a few metals and metal compounds can be magnetized. On the contrary, degaussing: When the magnetized material is subjected to external energy, such as heating and impact, the magnetic direction of each magnetic domain will become inconsistent and the magnetic property will weaken or disappear. This process is called demagnetization. The so-called magnetic refers to the ferromagnetism that a magnet has. In addition to metal iron also includes metallic nickel, cobalt, some rare earth metals, as well as some oxides, compounds of these metals. Magnetism in physics also paramagnetic, anti-magnetic, anti-ferromagnetic, paramagnetic and diamagnetic material in nature, so the magnet becomes very strange.