Like poles repel each other and unlike poles attract each other. We do not find isolated poles in nature, they come in pairs, every North Pole is associated with a South Pole, and visa versa. Therefore a bar magnet has two poles, a North Pole and a South Pole. Sources of Magnetism There are three sources of magnetism, or magnetic fields. Electrons, protons and neutrons are intrinsically magnetic.
Electric currents produces magnetic fields.
When we use electric currents to produce magnets, we call them electromagnets. They are important in electric motors. The magnetism in iron and permanent magnets is due to the intrinsic magnetism of electrons. In these materials some of the electrons will orient so that their magnetic poles align and add to produce larger poles. In materials like copper and aluminum the electrons do not orient this way and they are not magnetic.