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
Ian Cullimore Ian Cullimore wrote parts of the PCMCIA driver stack for (NetWare) PalmDOS 1.0, a variant of Digital Research's DR DOS, tailored specifically at battery powered mobile PCs in 1992. Ian Cullimore Ian Cullimore is an English-born mathematician and computer scientist who has been influential in the pocket PC arena. Cullimore has a degree in Mathematics from King's College London, and a PhD in Cognitive and Computer Science from the University of Sussex. He was the original founder (in 1985) and main inventor of the pocket PC which became the Atari Portfolio (originally known as the "DIP Pocket PC") in 1989.