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 "scientific" pocket-sized calculator the "B3-18" was completed by the end of 1975. In 1973, Texas Instruments (TI) introduced the SR-10, ("SR" signifying slide rule) an "algebraic entry" pocket calculator using scientific notation for $150. Shortly after the SR-11 featured an added key for entering Pi (π). It was followed the next year by the SR-50 which added log and trig functions to compete with the HP-35, and in 1977 the mass-marketed TI-30 line which is still produced. In 1978 a new company, Calculated Industries arose which focused on specialized markets. Their first calculator, the Loan Arranger (1978) was a pocket