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
SEAC (computer) SEAC (computer) SEAC (Standards Eastern Automatic Computer" or Standards Electronic Automatic Computer") was a first-generation electronic computer, built in 1950 by the U.S. National Bureau of Standards (NBS) and was initially called the "National Bureau of Standards Interim Computer", because it was a small-scale computer designed to be built quickly and put into operation while the NBS waited for more powerful computers to be completed (the DYSEAC). The team that developed SEAC was organized by Samuel N. Alexander. SEAC was demonstrated in April 1950 and was dedicated on June 1950; it is claimed to be the first fully operational stored-program