it convers 12 volts into 50,000 volts
Coil in electronics means wire wrap around some media the get different uses in applications. The above answer only pertains to coil on a car I suppose
It is part of the ignition system. in older cars, it is a single unit that is about the size of a coke can. In many newer cars, you have individual coil packs sitting on top of each spark plug.