Definition of citizens of ancient Greek polis

The restrictions on citizens are very strict: they must be male parents of the city-state, and they must be adult men. That is to say, four kinds of people cannot become citizens, one is women, the other is slaves, the third is foreigners, and the fourth is underage men of the city-state. Therefore, although there are about 200,000 people in Athens, there are only about 40,000 real citizens, so the democracy in ancient Greece is very developed, but it is only a minority democracy, which is called ".