Motor: A component which is able to amplify or control voltages or currents without mechanical or other nonelectrical command, or to switch currents or voltages without mechanical switches; examples include electron tubes, transistors, and other solid-state devices.

 

switch: Electrical device having two states: on, or closed; and off, or open. Ideally a switch offers a zero impedance to a current when it is closed, and it offers infinite impedance when open.

 

Light Bulb: A glass bulb containing a gas, such as argon or nitrogen, at low pressure and enclosing a thin metal filament that emits light when an electric current is passed through it