Answer:
One of the most important differences between ancient Greek democracy and ancient Roman Republicanism was institutional. For Greek thinkers, democracy was simply the rule of the many over the few, whereas aristocracy or oligarchy was the rule of the few over the many.
Athenian democracy developed around the fifth century B.C.E. The Greek idea of democracy was different from present-day democracy because, in Athens, all adult citizens were required to take an active part in the government. If they did not fulfill their duty they would be fined and sometimes marked with red paint.