| Resistor | A resistor is a device which resists the flow of current in a circuit, thus reducing the voltage available to the load. | The conventional regulator of a fan is a resistor. |
| Capacitor | A capacitor is a storage device which may be used as a timer, phase splitter etc. | All domestic fans have capacitors to split the phase of AC, the starter of a flourescent tubelight is a capacitor. |
| Inductance | An inductor is a device which resists changes in electric current passing through it. It consists of a conductor such as a wire, usually wound into a coil. Note that an inductor opposes change in current while a resistor just resists the flow of current. | The choke of a tube light is an inductor. |
| Transformer | A transformer is a device that transfers electrical energy through electromagnetic induction. Transformers may be used to increase or decrease the alternating voltages in electric power applications. | A voltage stabiliser, a mobile charger etc contain a transformer. |
| Diode | A diode is device that restricts the flow of electric current in only one direction. | Diodes are commonly used in rectifiers which are used to convert A.C. (alternating current) to D.C. (direct current) |
| Transistor | A transistor is a device usually made from semi-conductor material used to control the flow of current. | Transistors are commonly used as amplifiers and have variety of uses in electronic equipment like radio, tv etc. |