Computer science development of sophisticated computing equipment. Wilhelm Schickard designed and constructed the first working mechanical calculator in 1623. In 1673, Gottfried Leibniz demonstrated a digital mechanical calculator, called the Stepped Reckoner. He may be considered the first computer scientist and information theorist, for, among other reasons, documenting the binary number system. In 1820, Thomas de Colmar launched the mechanical calculator industry when he released his simplified arithmometer, which was the first calculating machine strong enough and reliable enough to be used daily in an office environment. Charles Babbage started the design of the first "automatic mechanical calculator", his Difference Engine, in
Digital Computer Association Digital Computer Association The Digital Computer Association (DCA) was established in November 1952 in Santa Monica, California. The organization held monthly 2–3 hour technical dinner meetings at local restaurants attended by early computer engineers and computer programmers. The founder was R. Blair Smith, a local IBM salesman. He had two reasons for starting the organization: to recruit the help of all 18 IBM 701 customers in combating copyright infringement, causing salaries to increase; and to provide a forum for exchanging software programs to eliminate duplication of effort. The DCA was loosely organized, met monthly, held an annual party and put