The north and south poles, often called the negative and positive sides, of a magnet are determined by using the directional properties of magnets. The north pole of the magnet is attracted to Earth's geographical north pole, and the south pole is attracted to Earth's geographical south pole.
One way to determine the north and south poles of a magnet is to hang the magnet by a light string and allowing it to hover freely and horizontally. The north pole of the magnet points toward Earth's north pole. Placing the magnet on a lightweight platform, such as a piece of foam, and then floating it on a liquid surface, also shows the north pole and south poles based on the directional properties of the magnet.