So, these things are baffling my mind. I understand they are a good storage of kinetic energy, and help keep momentum of motion. What I cannot get my head around is, how are they started say within a car, also I assume once the engine is turning over, why is the flywheel needed, so what is the purpose of it? This may sound really retarded to some people, but I just cannot picture how it comes into play. Any information or for someone to explain these questions would really clear this mess inside my head.