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 Packet Reporting System the IBM Personal Computer. During the early 1990s, CETS (then known as the Automatic Position Reporting System) continued to evolve into its current form. As GPS technology became more widely available, "Position" was replaced with "Packet" to better describe the more generic capabilities of the system and to emphasize its uses beyond mere position reporting. APRS (Automatic Packet Reporting System), is a digital communications protocol for exchanging information among a large number of stations covering a large (local) area, often referred to as "IP-ers". As a multi-user data network, it is quite different from conventional packet radio. Rather than using