This book attempts briefly to solve the mystery of DNA, the giant molecule found in all living cells and some viruses -- a phenomenon which has captured the interest of scientists concerned with virology, biochemistry and genetics. DNA may provide the key to the mystery of human life and this fantastic idea motivates much of the research. Information is given on what DNA is, where it is found and more important, how it works. Photographs and straight exposition outline the chemistry and geometry of DNA, how it carries hereditary factors and mutations, and how it helps build proteins. Instructions on how to make a model of DNA concludes a survey geared for those with science leanings.