Andrew Pettegree, a professor of modern history at the University of St. Andrews, discussed how Martin Luther used printing in order to communicate his message, as he relates in the book, "Brand Luther: How an Unheralded Monk Turned His Small Town into a Center of Publishing, Made Himself the Most Famous Man in Europeâ€â€and Started the Protestant Reformation." Learn more through the publisher's website at www.penguinrandomhouse.com.