ElladanKenet
'Star Destroyer' is a common name used to describe no less than 12 different kinds of vessel. In fact, just in the line of Destroyers, there are 5 kinds of Star Destroyer: MK I, MK 2, MK 3, Tector, and Dominator.
I suddenly realized how wrong this statement was. He managed to completely forget the Victory series of Star Destroyers, as well as the Venator series.
So there are this at least 11 classes of Imperial Star Destroyers:
Allegiance, Imperial I, Imperial II, Imperial III, Tector, Dominator, Victory, Victory II, Victory III, Harrow, and Venator.