* Conductor: A material that allows electricity to flow easily (like a wire).

* Switch: A device that can open or close the circuit, controlling the flow of electricity.

* Electric Cell: A source of electrical energy (like a battery).

* Resistor: A component that resists the flow of electricity.

In a series circuit, all components are connected in a single loop. The electricity flows through each component one after the other. This is in contrast to a parallel circuit, where components have separate paths for the electricity to flow.