Ryan Holiday is an American author, marketer, and entrepreneur.He is a media strategist, the former Director of Marketing for American Apparel and a media columnist and editor-at-large for the New York Observer.Holiday is the author of several books and has written for Forbes, Fast Company, The Huffington Post, The Columbia Journalism Review, The Guardian, Thought Catalog, Medium.com and the New York Observer, where he is the media columnist.Holiday, through his books, articles and lectures, has been credited by the New York Times with the increasing popularity of stoicism.He was also described as "leading the charge for stoicism," which has been noted for gaining traction among Silicon Valley entrepreneurs.