You may already know many things about magnets.
You may know that every one has a north pole (N) and a south pole (S). That unlike poles are attracted to each other. That like poles repel, or push away from, each other. That the strongest parts of a magnet are near the poles. That if you break a magnet into pieces, north and south poles form on each part. That magnets pull in coins, thumbtacks, and other objects. These kinds of objects are made of ferromagnetic materials like iron. (The word ferro comes from Latin. It means “iron.”) It’s great to know all this. But what really causes magnetism? Are you ready to think small? Let’s go.