Go on Clive. Let's throw in conventional and electron flow, just for fun. So to boil the answer down, as long as the Bu**er starts and gets me to where I want to go who cares? Though I have got an electronic ignition to fit, at that point it does matter. The coil acts as a transformer. The opening and shutting of the points causes an oscolating magnet feild so allows the coil to boost the voltage. The higher voltage allows the current to jump the air gap on the plugs, this creates the spark. The same sort of system also creates radio waves, hence the sheilding needed particullaly in FFR vehicles. The heat bit is because a Cathode, ie Negative polarised plate will excite electrons when it is warm, so they will jump to an Anode or positve plate. That's why the old thermionic valves had a heater in the valve and sets had to litterally 'Warm Up'. Electrons being a negativley charged particale will flow to a positive Anode. Unlike charges attract. That is Electron flow. In practice it dosen't matter to much, which is why most people work on a current going from positive to negative, conventional flow.