who invented the first automatic calculater in 1642
Pascal's calculator Pascal designed the machine in 1642,[3] and after 50 prototypes, he presented it to the public in 1645, dedicating it to Pierre Séguier, then chancellor of France.[4] Pascal built around twenty more machines during the next decade, many of which improved on his original design. In 1649, King Louis XIV of France gave Pascal a royal privilege (similar to a patent), which gave him the exclusive right to design and manufacture calculating machines in France. Nine Pascal calculators presently exist;[5] most are on display in European museums.
Calculator Another calculator introduced in 1965 was Bulgaria's ELKA 6521,[20][21] developed by the Central Institute for Calculation Technologies and built at the Elektronika factory in Sofia. The name derives from ELektronen KAlkulator, and it weighed around 8 kg (18 lb). It is the first calculator in the world which includes the square root function. Later that same year were released the ELKA 22 (with a luminescent display)[20][22][23] and the ELKA 25, with an in-built printer. Several other models were developed until the first pocket model, the ELKA 101, was released in 1974. The writing on it was in Roman script, and it was exported to western countries.[20][24][25]