The Greeks were the earliest discoverers of much of the knowledge that went on to lay the foundations of scientific studies for thousands of years and one of the most important figures from that period is undoubtedly Eratosthenes, who was a mathematician, geographer as well as an astronomer of rare quality. Additionally he was also a music theorist which well and truly shows the sort of versatile knowledge and gifts that he possessed. Eratosthenes was responsible for bring to notice some of the most important discoveries in geography, astronomy and mathematics. Born in the Cyrene, the young lad was remarkably curious from an early age. He pursued higher education from Athens where he was taught by the best teachers of the day. Aristo of Chios and Arcesilaus in particular left a lasting impression on the budding philosopher. His reputation as a mathematician was affirmed when he measured the circumference of the earth using the shadows cast by the sun. He also made immense contribution to the field of geography by demarcating the five different climate zones existing in the earth. In fact the term geography was also coined by this eminent scientist. It can be unarguably said that this erudite scientist made discoveries that were way ahead of his time. Read on to know more about his life and works.