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The Casio DC-750 Data-Cal 50 — Calculator and Data Bank
The Casio DC-750 combined a scientific calculator with a data bank for storing personal information — an early example of the convergence between calculation and information management that would eventually produce dedicated PDAs. Casio was a pioneer in adding data storage to calculators, recognising that users who carried calculators also needed to store phone numbers, addresses, and notes. These combined calculator-organiser devices were popular throughout the late 1980s before dedicated organisers and PDAs provided more sophisticated information management.