About the author: About the writer, Mark S. Greenberg, absolutely nothing is known. He is not the Mark Greenberg who is a real estate agent nor the Mark Greenberg who is Head of Cardiology nor even the neurosurgeon, Mark S. Greenberg, who wrote the book (Not this one!) on it. He is not the photojournalist Mark Greenberg who did do a book on the Amazon nor the political reporter Mark Greenberg who has a book about Obama. He is not the Mark Greenberg who is a lawyer and MD nor the one who is Provost in Utah nor the one who holds a Chair in Preventive Science at Penn State, tempting as it might be to think that is the one he is. Whoever or whatever you think the writer might be, he is someone and something else. If you ever had Mark Greenberg as a friend, neighbor, relative, co-worker, enemy, casual acquaintance or lover (Unlikely!), this one is not that one.