A magnet is an object that can generate a magnetic field. A magnetic field is an intangible force field that can exert a force on other objects around it, which is called magnetic force. Magnetic force can attract or repel certain objects, which are called magnetic substances. The most common magnetic substances are metals such as iron, nickel, and cobalt.

Magnets have two special parts called magnetic poles. One magnetic pole is called the North Pole, and the other is called the Guide Pole. If a hanging magnet is placed on Earth, it will automatically rotate, causing the N pole to point to the north of the Earth and the S pole to point to the south of the Earth. This is because the Earth itself is a huge magnet, with two magnetic poles located near the north and south poles. The magnetic field generated by the Earth is like a compass, which can help us determine direction.