The first Soviet calculators had their own operational language, with unique features like Svetlana’s C3-07 combination functions and eight-element display. The transition from fixed to floating point calculators led to more advanced models like B3-18, offering trigonometry and algebra functions. The B3-21 became the first Soviet programmable calculator, with 60 programming steps and the ability to play games. The calculator revolutionized production control, leading to desktop variants like MK-46 and MK-64 for automated operations. Despite being expensive, the B3-21 became a popular choice in Russia for its innovative features and automation capabilities.
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