Ancient Greek Mathematics History

600 B.C.: Thales introduces deductive geometry. It was developed over the years by Pythagoras and the Pythagoreans, Plato, Aristotle, Euclid, and others.
540 B.C.: Pythagoras does geometrical work.
450 B.C.: Zeno of Elea (489 B.C. - 430? B.C.) formulates Zeno's paradox.
380 B.C.: Plato, whose ideas were influenced by the Pythagoreans, is writing philosophy.
340 B.C.: Aristotle is writing philosophy.
300 B.C.: Euclid compiles, organizes and systematizes geometric ideas which had been discovered and proven into thirteen books, called The Elements.
240 B.C.: Eratosthenes determines that the Earth is spherical and computes its diameter.
225 B.C.: Archimedes (287 B.C. - 212 B.C.) does work on circles, spheres, areas, infinite series, and other things.
225 B.C.: Appolonius works on conic sections.

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The main number system used by the Greeks during this period was the Attic system.