Euclides (age unknown)
Euclid (c. 325 BC-c. 265 BC), ancient Greek mathematician. Euclid taught mathematics at Alexandria, Egypt, but little more is known about his life. He is most famous for his Elements, a mathematical treatise that became the centre of mathematical teaching for 2000 years. Within the 13 volumes of the treatise, Euclid deduces the properties of geometrical objects from basic axioms, and describes some fundamental number theory.