Finding out about electricity, what it does and how it does it, is fascinating. Not only that, but it's such a mega-important part of our lives, understanding it better is vital! That's one of the reasons you get to test out electric circuits at school (and at home if you're lucky enough to have a kit!).
In a simple series circuit (where the components are connected in one complete loop) the flow of electricity (the current) is affected by the wires and components.
Adding more components results in less current for each one. This makes bulbs dimmer and motors slower.
FACT: it is harder for current to flow through long, thin wires.
FACT: short, thick wires make it easier for the current to flow.
OK, with all that in mind, let's have a look at current, wires and components.