When battery, bulb, and switch are interconnected with the use of wire, a circuit is formed.
In a circuit, a battery serves as a power source. A chemical energy is stored within it and can be converted to electric energy.
A bulb converts electrical energy to light. When electric current flows through it, the bulb produces light.
A switch stops and allows the electricity to flow through the circuit. When the switch is at OFF state, discontinuity along the circuit connection occurs which result to no current flow. And when in ON state, there is no breaks along the connection and the electricity flows through the circuit.
And the wire serves as a pathway for the electricity. It is where the electric energy flows.