What Magnets Do

A magnet pulls on certain metals without even touching them. Iron, nickel, and cobalt feel the pull; plastic, wood, and aluminum cans do not. The pulling happens through an invisible field that surrounds the magnet.

Every magnet has two ends, called the north pole and the south pole. Opposite poles attract - north pulls toward south. Matching poles repel - put two north ends together and they push each other away. That push is strong enough to float a toy train on a track.

Earth itself works like a giant magnet, which is why compass needles swing around to point north. Sailors used compasses to cross oceans long before maps were accurate, and birds may use the same field to find their way home.