You may already know lots of facts about magnets.
That every magnet has a north pole (N) and a south pole (S). That unlike poles attract each other. That like poles repel each other. That the strongest parts of a magnet are near the poles. That if you break a magnet into parts, north and south poles form on each part. That magnets attract coins, thumbtacks, and other objects made of ferromagnetic materials like iron. (The word ferro comes from Latin and literally means “iron.”) Knowing all these facts is great. But what actually causes magnetism? To appreciate the answer, be ready to think small.