I know the ground wire takes unused electricity to the ground but what is the purpose of the neutral wire?
The neutral returns unused electricity back to the source where as the ground provides a pathway for an electrical short to return back to the panel and then to an earth ground.
The neutral wire is supposed to be the wire that functions to take the current from the hot side back to the power line. The ground is there as a safety measure - in 3 wire appliances, the ground is usually connected to the housing. It is there in case some part of the hot circuit becomes shorted to the appliance housing - if that happens on a modern 3-wire electrical system, it will cause the breaker to trip. Or, if the appliance is plugged into a ground fault interrupter GFI, that will generally trip first, before the breaker.
