How works a car or vehicle ignition system

Spark plug

                      We have understood that how works a petrol engine through How works motor vehicle-engines part-1 and the How works Two stroke petrol engine(to view the article click on the link here) . I had  described the combustion process in the cylinder and to start the combustion of the air-fuel mixture we needed a thing that called as 'spark plug'.
                      Yes we know  that the spark plug gives a spark to the air-fuel mixture to start the combustion process. So, if a spark plug has to give a spark, how does the system of the engine  designed for the sparking process will work? Yes, I am going to explain now about it.
                         The system properly designed for producing a spark is called as 'ignition system'. now let's see about the ignition system.