Hi Dear,

Ignition coil is an induction coil that converts current from a battery into the high-voltage current required by spark plugs. Ignition coil  transforms the low voltage energy of the battery into a high voltage signal, in order to create a spark at the terminal of the plug. Following are few types of ignition coil:

• distributorless ignition system (DIS)
• Electronic Ignition Coil
• Conventional Ignition Coil
• coil-on-plug (COP) ignition coil

Good Luck

Hi,
The design of conventional ignition coil is similar to that of transformer. The ignition coils task is to induce a high voltage from low voltage.
Alongside the iron core, the main components are the primary winding, secondary winding and the electrical connections.
The amount of high voltage depends on speed of change in magnetic field, number of windings in secondary coil, strength of magnetic field.
Hope it helps.