Simple Circuits
A circuit is a complete loop that lets electricity flow from a power source (like a battery), through components, and back again. If the loop is broken anywhere, the electricity stops.
What a circuit needs
Every circuit needs a power source, a conductor (like wire) to carry the electricity, and something for it to power, like a bulb or buzzer.
Switches
A switch is a gap in the circuit that can be opened or closed. Closing it completes the loop and lets electricity flow; opening it breaks the loop and stops it.
Practice
If a bulb doesn't light up, what are two possible reasons why?