A device used to store an electric charge, consisting of one or more pairs of conductors separated by an insulator.
A semiconductor device with two terminals, typically allowing the flow of current in one direction only. A thermionic tube having two electrodes (an anode and a cathode).
An inductor, also called a coil or reactor, is a passive two-terminal electrical component which resists changes in electric current passing through it. It consists of a conductor such as a wire, usually wound into a coil. When a current flows through it, energy is stored temporarily in a magnetic field in the coil.
A resistor is a passive two-terminal electrical component that implements electrical resistance as a circuit element. Resistors act to reduce current flow, and, at the same time, act to lower voltage levels within circuits