A kind of rock called lodestone has eerie power to attract bits of iron through some kind of invisible force. Today, we call that phenomenon magnetism. How Magnetism Works Magnetism is one aspect of the fundamental force called electromagnetism. Electricity, which is the flow of electrons through a wire or in a beam across open space, is the other.
Magnetism arises when electrically charged things move.
No motion, no magnetism. . . Earth has a magnetic field because, deep within its core, molten metals carrying electrical charges circulate in patterns. Earth's field also deflects charged particles, just as the field in a TV picture tube deflects moving electrons. That's good news for terrestrial life. For one thing, all particles spin.