Astrobiology -- which studies the intimate relationship between life and the cosmos -- is a fast-growing field that touches on aspects of cosmology, astrophysics, and chemistry. In the first scholarly overview of this dynamic field, biochemists Kevin W. Plaxco and Michael Gross tell the story of life from the Big Bang to the present. Emphasizing the biochemical nature of astrobiology, Plaxco and Gross examine the origin of the chemical elements, the events behind the developments that made our Universe habitable, and the ongoing sustenance of life. They discuss the formation of the first galaxies and stars, the diverse chemistry of the primordial planet, the origins of metabolism, the evolution of complex organisms, and the feedback regulation of Earth's climate. They also explore life in extreme habitats, potential extraterrestrial habitats, and the search for extraterrestrial life. This broadly accessible introduction captures the excitement, controversy, and evolution of the dynamic young field of astrobiology. It shows clearly how scientists from different disciplines can combine their special knowledge to enhance our understanding of the Universe we inhabit.