This text explains in a step-by-step fashion why DNA forms specific structures, the nature of these structures and how they fundamentally effect the biological processes of transcription, recombination and replication.
I was more looking for the functions of DNA in the generation of proteins but this book was more about the structure of DNA more than anything else. It's very comprehensive, a little bit difficult for me since it involves a lot of calculations for the DNA's lengths and the different arrangements. Nonetheless, it was a very useful text book for understanding DNA (and not its functions).