The diagram shows a simple circuit of a battery, wires, a switch and a lamp. The switch works by breaking the circuit.
Oscilloscope An oscilloscope is used to display the shape of electrical signals - showing how they vary with time. It can be used to measure voltage and time periods.
A NOT gate can only have one input. The o on the output means not. The output of a NOT gate is the inverse (opposite) of its input, so the output is true when the input is false. A NOT gate is also called an inverter.
Electricity is the flow of charge around a circuit carrying energy from the battery (or power supply) to components such as lamps and motors.