Magnets (Greek: μαγνήτις λίθος magnetis lithas, "magnesia stone") are objects that have a special attraction. This power of the magnet is called magnetism. Creates a magnetic field due to the magnetism of the magnet. This magnetic field is invisible but through it almost all the properties of the magnet are revealed; It is a force that attracts the ferromagnetic material around it and attracts or repels other magnets. The first permanent magnets were made of steel.
A null magnet made of alnico. Because the magnet is null in shape, its two magnetic poles are close together. This shape creates a very strong magnetic field at the poles that enables the magnet to lift a heavy piece of iron.