Overview: You’re probably familiar with the basics of magnets already: They have a north pole and a south pole. Two of the same pole will repel each other, while opposites attract. Only certain materials, especially those that contain iron, can be magnets. And there’s a magnetic field around Earth, which is why you can use a compass to figure out which way is north. In this episode of Crash Course Physics, Shini takes us into the world of magnetism!