Is Earth Actually Flat?
The flat Earth model is an archaic conception of the Earths shape as a plane or disk. Many ancient cultures subscribed to a flat Earth cosmography, including Greece until the classical period, the Bronze Age and Iron Age civilizations of the Near East until the Hellenistic period, India until the Gupta period and China until the 17th century. That paradigm was also typically held in the aboriginal cultures of the Americas, and the notion of a flat Earth domed by the firmament in the shape of an inverted bowl was common in pre-scientific societies.
The idea of a spherical Earth appeared in Greek philosophy with Pythagoras , although most Pre-Socratics retained the flat Earth model. Aristotle provided evidence for the spherical shape of the Earth on empirical grounds by around 330 BC, writing as if this idea was already well-accepted in his day and time. Knowledge of the spherical Earth gradually began to spread beyond the Hellenistic world from then on. (source : wikipedia