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
Automatic Digital Computer M-1 Automatic Digital Computer M-1 The project to build the M-1 or Automatic Digital Computer (ADC) M-1 () was completed at the end of 1951, at the Energetics Institute of the USSR Academy of Sciences. In charge of the Laboratory of Electrosystems was Isaak Semenovich Brook (or Bruk), who obtained the first domestic patent with the title "Digital Computer with Common Bus" in 1948. Work to build the computer based on Brook's design began in 1950. Parts were very difficult to get due to postwar rationing. On the other hand, due to availability of copper oxide diodes which were brought as