Apollonius of Perga (c. 262-190 B.C.) - known as 'The Great Geometer', great influence on the development of mathematics, famous book Conics introduced terms such as parabola, ellipse and hyperbola. Steiner, Jakob (1796-1863) - Was one of the greatest contributors to projective geometry. Riemann, Georg Friedrich Bernhard (1826-1866) - Theory of functions, non-Euclidian geometry, relativity theory, Famous for the Riemann hypothesis about the behavior of zeros of the Riemann zeta function, which he showed determines the distribution of prime numbers. Desargues - Girard Desargues (1591-1661) - Founder of projective geometry, his work centred on the theory of conic sections and perspective. Heron of Alexandria (ca. 75 AD) - Greek mathematician who was mainly interested in practical studies in mechanics and engineering, best known for Heron's Formula Klein, Felix (1849-1925) - Plücker's assistant at Bonn who studied Analytic Geometry, describing geometry as the study of properties of figures which remain invariant under a Group of Transformations. He systemized Non-Euclidean Geometry. Monge, Gaspard - Conte de Péluse (1746-1818) - The father of differential geometry, he devised a system called Geometrie descriptive, now known as orthographic projection, the graphical method used in modern mechanical drawing.