Current electricity is the form of electricity which makes all of our electronic gizmos possible. This form of electricity exists when charges are able to constantly flow.
In order to flow, current electricity requires a circuit: a closed, never-ending loop of conductive material. A circuit could be as simple as a conductive wire connected end-to-end, but useful circuits usually contain a mix of wire and other components which control the flow of electricity.
The only rule when it comes to making circuits is they can’t have any insulating gaps in them.
If you have a wire full of copper atoms and want to induce a flow of electrons through it, all free electrons need somewhere to flow in the same general direction. Copper is a great conductor, perfect for making charges flow. If a circuit of copper wire is broken, the charges can’t flow through the air, which will also prevent any of the charges toward the middle from going anywhere.