Making Simple Robots, 2nd Edition

• A circuit also needs a component that runs on electricity. This

can be a light, a motor, a speaker, or other components that

need electricity to work. It is known as the circuit’s load.

• A power source like a battery has a negative terminal (end)

and a positive terminal. Components have negative and

positive terminals too. For some components, it doesn’t matter

which end is which. But an LED will only light if the positive end

is facing the positive end of the battery. This is called polarity.

• To prevent a short circuit, cover the circuit with insulation,

material that isn’t friendly to electricity. Insulation keeps the

electricity flo ...