Objects containing magnets include: speaker, tape recorder, mobile phone, bag magnetic buckle, radio, nuclear magnetic resonance instrument, magnetic hook, computer, magnetic whiteboard, water inlet or drain valve of automatic washing machine, TV set, magnetic stripe of refrigerator door, earphone, stereo, etc. Magnets can generate magnetic fields and adsorb ferrous metals, such as nickel, iron and cobalt.

Magnets are made up of atoms such as iron, cobalt and nickel. Their atoms have special internal structures and have their own magnetic moments. Hang the midpoint of the bar magnet with a thin wire. When it is at rest, its two ends will point to the south and north of the earth respectively. One end pointing to the north is called North Pole or N Pole, and the other end pointing to the south is called Guiding Pole or S Pole.

Magnets can be used to attract iron and achieve the effect of removing iron. They are also used in many fields, such as compasses and attracting light and small objects. Electromagnets can be used as electromagnetic relays, motors, generators, electroacoustic, magnetic therapy, magnetic levitation, nuclear magnetic resonance and so on.

Magnets can be divided into "permanent magnets" and "non-permanent magnets". Permanent magnets can be natural products, also known as natural magnets, or artificial. Non-permanent magnets, such as electromagnets, are magnetic only under certain conditions.