Most substances are composed of molecules, which are made up of atoms, and atoms consist of a nucleus and electrons. Inside an atom, electrons spin and orbit around the nucleus. Both of these movements generate magnetism. However, in most substances, the directions of electron movements are different and chaotic, causing the magnetic effects to cancel each other out. Therefore, most substances do not exhibit magnetism under normal conditions.

Iron, cobalt, nickel, or ferrites, among other ferromagnetic materials, differ in that their internal electron spins can spontaneously align within a small range, forming a spontaneously magnetized region known as a magnetic domain.

When ferromagnetic materials are magnetized, their internal magnetic domains align neatly and uniformly, enhancing the magnetic property, thus forming a magnet. The process of attracting iron with a magnet is the process of magnetizing the iron block. The magnetized iron block and the magnet attract each other due to opposite poles, causing the iron block to firmly adhere to the magnet. We say the magnet has magnetic properties.