Apollonius of Perga (Greek: Ἀπολλώνιος ὁ Περγαῖος; Latin: Apollonius Pergaeus; c. 240 BC – c. 190 BC) was an Ancient Greek geometer and astronomer known for his work on conic sections. Beginning from the contributions of Euclid and Archimedes on the topic, he brought them to the state prior to the invention of analytic geometry. His definitions of the terms ellipse, parabola, and hyperbola are the ones in use today. Gottfried Wilhelm Leibniz stated “He who understands Archimedes and Apollonius will admire less the achievements of the foremost men of later times.”