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Answer:

Most material is non-magnetic. It is composed of molecules made of atoms, each of which have electrons orbiting nuclear protons, but where the motion of one electron, essentially a tiny electric current, generates a magnetic field that is cancelled by the magnetic field generated by the motion of another electron. In magnetic materials this cancellation is incomplete, and so the atoms of the material have small net electric currents and they thus generate small magnetic fields. For various reasons having to do with the intricacies of atomic physics, this tends to happen for certain substances, like cobalt, nickel, and, of course, iron. Within these magnetic materials, the magnetic fields of the various atoms exert torques on the electric currents of their neighboring atoms, causing the atoms to align and their magnetic fields to add together constructively. As a result, the material exhibits a magnetic field. It is a ‘magnet’. Most magnets are like the bar magnet shown in the illustration, having a simple 'dipole' arrangement of a 'north' pole, where the field diverges, and a 'south' pole, where the field converges.

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