Internationally bestselling author, Wharton School of the University of Pennsylvania Professor, Jonah Berger shares insights from his best selling books: Contagious: Why Things Catch On, Invisible Influence: The Hidden Forces that Shape Behavior, and The Catalyst: How to Change Anyone's Mind, which have sold over a million copies and in print in over 35 countries around the world. Jonah is considered a world-renowned expert on change, word of mouth, viral marketing, social influence, and how products, ideas, and behaviors catch on.