Electrical appliances have combinations of the following parts in arrangements that do something useful for us:

COILS – There are many types of coils that do different jobs. Electricity can be changed to heat when it passes through certain kinds of metal. Antenna coils convert radio signals to electricity. Tape recorders and computers use tiny electromagnet coils to put information on magnetic tapes and disks.

LIGHT BULBS – Incandescent light bulbs have a coil of wire that glows because it gets hot when electricity flows through it. Florescent tubes are coated on the inside with a chemical that glows when exposed to electricity.

LEDs – Light emitting diodes are used for small indicator lights that show when an appliance (or one of its functions) is turned on. Some smaller appliances, like calculators, may have an LCD (liquid crystal display). These are not as bright as LEDs but they use less electricity.

MOTORS – Motors change electricity into motion by using electromagnets to spin a shaft. Many appliances have pumps, fans, or gears that need a motor to make them turn.

BUZZERS, SPEAKERS, and BEEPERS– These change electricity into sound. Many appliances give audio signals to let people know when a job is finished or when a problem has come up. Speakers have electromagnetic coils that are attached to a cone, making it vibrate. Beepers are electronic noisemakers that produce sound by vibrating small crystals.