Dennis C. Hayes

Dennis C. Hayes is best known as the co-founder of Hayes Microcomputer Products, whose modems helped millions connect to the Internet and whose modem commands became an industry standard.

Hayes attended the Georgia Institute of Technology before leaving in the mid-1970s to work at National Data Corporation, where he set up modem connections and met Dale Heatherington. They developed a modem for early microcomputers and founded D.C. Hayes Associates in January 1978; the business later became Hayes Microcomputer Products. Early products included modem boards for S-100 computers and for the Apple. The company then introduced its external Smartmodems, which connected over an RS-232 line and were controlled with “AT” commands.

Hayes modems earned a reputation for reliability and broad compatibility, and the company grew to control more than half of the modem market. Heatherington retired at 36, while Hayes continued running the business. Increasing competition, shrinking profit margins, and cash shortages undermined the company: it entered bankruptcy in 1994, and its operations closed in January 1999. By 2003 Hayes was consulting for small businesses in New York and volunteering as chairman of the U.S. Internet Industry Association; that year he was inducted into a computer industry Hall of Fame.