Calculator watch financial functions (in the Casio CBA-10). Usually calculator watch operates with eight digits number, however, calculator watch can operate with 6 digits (for example, Casio C-801) or 10 digits (Casio CBA-10) numbers. Calculator watches first appeared in the mid 1970s introduced by Pulsar (1975, then a brand of the Hamilton Watch Company) and Hewlett Packard. Several watch manufacturers have made calculator watches over the years, such as Pulsar and Timex, but the Japanese electronics company Casio produced the largest variety of models. In the mid-1980s, Casio created the Databank calculator watch, which not only performed calculator functions, but also stored
Calculator realised in the mid-1950s that the future of calculators lay in electronics. They employed the young graduate Norbert Kitz, who had worked on the early British Pilot ACE computer project, to lead the development. The ANITA sold well since it was the only electronic desktop calculator available, and was silent and quick. The tube technology of the ANITA was superseded in June 1963 by the U.S. manufactured Friden EC-130, which had an all-transistor design, a stack of four 13-digit numbers displayed on a cathode ray tube (CRT), and introduced Reverse Polish Notation (RPN) to the calculator market for a price