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
Sumlock ANITA calculator "no binary stunts here!". Similar to the Comptometer calculating machines of the time, the ANITA had a full keyboard, a feature that was unique to it and the later Sharp CS-10A among electronic calculators. Being silent and very quick in operation, and the only electronic desktop calculator available, the ANITA sold well, reaching nearly 10,000 units per year by 1964. 1961 was a doubly notable year for the Bell Punch Company since it then also amalgamated its calculator division with the British operation of Comptometer Corporation of Chicago, U.S.A. (formerly the Felt & Tarrant Manufacturing Co.), to form Sumlock Comptometer