Greek communities, known as polis, were city-states that formed the foundation of ancient Greek civilization. Each polis operated independently, with its own government, laws, and customs. Major examples include Athens, known for its democratic system, and Sparta, famous for its military discipline. These communities fostered a sense of identity and belonging among their citizens. The social structure of Greek communities was diverse, including free citizens, women, and slaves. Citizens participated in civic life, engaging in politics, philosophy, and the arts. Festivals and religious ceremonies, such as the Olympic Games, were significant events that united different polis and celebrated shared cultural values.