Outlet Add-on
Fundamentals
Electricity will only flow in a complete circuit. If you come into contact with an electrical conductor, your body might complete the circuit.
Electricity always tries to return to its source
Electricity will take all available paths to complete a circuit. It takes preference to path with less resistance and more current will flow in that path.
Batteries come with a + and - sign, to complete the circuit, picture a current coming out of “-“ and into the light, then back into “+”, completing the circuit. The wire that carries the current into the light is your hot wire, and the wire that carries the current back is your neutral; back to the source.
If we look at a residential electrical system in the US, we will find 1 Neutral and 2 hot wires, and some ground wires.