# Apollonius of Perga

**Apollonius of Perga** (about

262 BC - about

190 BC) was a Greek geometer, noted for his writings on

conic sections. It was Apollonius who gave the

ellipse, the

parabola, and the

hyperbola the names by which we know them. The hypotheses of eccentric orbits, or equivalently, deferent and epicycles, to explain the apparent motion of the planets and the varying speed of the Moon, are also attributed to him.