In this book, his last, Carl Sagan shows once again his extraordinary ability to interpret the mysteries of life and the majesty of the universe for the general reader. In Billions and Billions Sagan applies what we know about science, mathematics, and space to everyday life as well as to the exploration of many essential questions concerning the environment and our future. Ranging far and wide in subject matter, he takes his readers on a soaring journey, from the invention of chess to the possibility of life on Mars, from Monday Night Football to the relationship between the United States and Russia, from global warming to the abortion debate. And, on a more intimate note, we are given a rare glimpse of the author himself as he movingly describes his valiant fight for his life, his love for his family, and his personal beliefs about death and God.