I would like to acknowledge Mario Ballano, Ruben Santamarta, and Victor Manual Alvarez, as well as all my friends who helped me write this book, shared their opinions and criticisms, and discussed ideas. I am most thankful to my girlfriend for her understanding and support during the time that I spent on this book. Many thanks to Elias Bachaalany; without his help, this book would not have been possible. Also, special thanks to everyone at Wiley; it has been a great pleasure to work with you on this book. I am grateful for the help and support of Daniel Pistelli, Carol Long, Sydney Argenta, Nicole Hirschman, and Marylouise Wiack.