David Weinberger (born 1950) is an American technologist, professional speaker, and commentator, probably best known as co-author of the Cluetrain Manifesto (originally a website, and eventually a book, which has been described as "a primer on Internet marketing" . Weinberger's work focuses on how the Internet is changing human relationships, communication, knowledge and society. A philosopher by training, he holds a Ph.D. from the University of Toronto and taught college from 1980-1986. He was a gag writer for the comic strip "Inside Woody Allen" from 1976-1983. He became a marketing consultant and executive at several high-tech companies, and currently serves as a fellow at the Berkman Center for Internet and Society at Harvard Law School, where he co-teaches a class on "The Web Difference" with John Palfrey. In addition, he is Co-Director of the Harvard Library Innovation Lab at Harvard Law School.