Right, so what do we know about electricity so far?
A circuit carries electrical energy from its source to a device.
Overhead cables are carried by large metal pylons. They are components in the large circuits from the power station to our homes, schools and workplaces.
Our homes have mains circuits, which carry electricity to every room, and you plug devices into these circuits.
Electrical appliances also have smaller circuits inside them.
To allow the electricity to flow, the circuit must be a complete loop, with no gaps. Circuits are made using conducting materials (like metal wires) which allow the electricity to flow, and insulating materials (plastics) which stop the flow of electricity.
Are you ready to have a go at some questions on circuits now?
You can look back at this introduction at any point by clicking on the red help button on the screen.