Daniel Mullen : The previous century has helped scientifically better understanding of the mechanisms of functioning of living beings: the decryption (although incomplete) of the human genome and the discovery of extra-solar planets (over sixty-present). This new century must meet him at the origin of life on earth and its extension in the universe. This program coincides exactly with the recent scientific discipline called astrobiology, which is therefore exploring the origin of life (there are over 3.5 billion years), its evolution and its distribution on the earth and in the universe. Fundamentally multidisciplinary, it brings together researchers interested in the problem of the origin of life in general (astronomers, climatologists, chemists, geologists ...) within a CNRS team and a school exobiology. The book is the manual for this new science. Each researcher worked on writing a chapter in his specialty, the relevance of the ideas was guaranteed by several reviewers of the specialty. Developed particularly the state of the young Sun, falling interplanetary matter and the origin of the water, the formation and evolution of the atmosphere and oceans ... The book, so far unique, brings to curious about the world the essential keys to understand it.