This text presents the essential of affine, Euclidean, projective and hyperbolic geometries in a transformational perspective as inaugurated by F. Klein. It originated from the author's 2-volume textbook in French 'Géométrie Affine et Projective' Editions Ceda, Abidjan. It can be used as a one semester Modern Geometry course for second year college math students, especially those who are prospective high school mathematics teachers. The text starts with a concise historical development of geometry from the times of Thales and Euclid to the 20th century, highlighting significant discoveries in Geometry. Honoré P. Mavinga is a Professor of Mathematics. He is a native of the Democratic Republic of the Congo.He received his Master's and Doctoral degree at the Université Catholique de Louvain in Belgium and an extended study diploma from the Université de Paris 5. Following his studies in Europe, he received a postdoctoral fellowship grant from the US state department for a semester at Princeton. He returned to Africa where he taught at Université de Kinshasa (Congo) then at Université d'Abidjan (Côte d' Ivoire). During that time he served as one of the 12 members of the board committee of the African Mathematical Union which held its initial Pan African Convention in Rabat (Morocco) in 1976. He also taught as visiting associate at the University of the South Sewanee Tennessee for one year and the next year at Cuttington College (Liberia). In 1989 he moved with his family to the USA where he taught at University of Wisconsin-Eau Claire, WI and more recently at Liberty University in Virginia. Honoré Mavinga confessed Christ publicly during the campaign 'Explo '84' sponsored by the Campus Crusade for Christ in Abidjan. He also enjoys cooking and singing.