The igition module is also refered to as the igniter. The module is the control unite that takes the information as to the location of the crankshaft to timing assembly. It synchronizes the two and tells the distributor when to fire the pulse to the spark plugs. These units are prone to failure and need to be isnstalled with lots of dielectric grease (between the module and the mounting location) which acts as a heat sink. Hope this helps.