Ancient Greek period can be divided into classical period and Hellenistic period. Hellenistic mathematicians were famous in spreading their discoveries throughout the world. Hellenistic period was great as many philosophers and mathematicians emerged during that age.
There were many famous Greek mathematicians like Pythagoras, Aristotle, Ptolemy and Euclid.
Pythagoras Theorem proposed by Pythagoras is in use even today.
‘Elements’ is the famous book of science written by Euclid. This was book was based on Geometry. The science of mathematics reached it pinnacle during Hellenistic period.