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
Software calculator computer was designed to run business application software such as payroll. Software specifically to perform calculations as its main purpose was first written in the 1960s, and the first software package for general calculations to obtain widespread use was released in 1978. This was VisiCalc and it was called an "interactive visible calculator", but it was actually a spreadsheet, and these are now not normally known simply as calculators. The Unix version released in 1979, V7 Unix, contained a command-line accessible calculator. Calculators have been used since ancient times and until the advent of software calculators they were physical, hardware