Electronic organizer Phones and PDAs. Electronic organizer An electronic organizer (or electric organizer) is a small calculator-sized computer, often with an in-built diary application but few other functions such as an address book and calendar. It normally has a small alphanumeric keypad and an LCD screen of one, two or three lines. Because of the advent of personal digital assistants, and later smartphones in the 2000s and 2010s respectively, both of which have a larger set of features, electronic organizers are rarely seen today. Casio digital diaries were produced by Casio in the early and mid 1990s, but have since been entirely
Mechanical calculator introduced in 1902 was the first of its type to use only ten keys, and became the first of many different models of "10-key add-listers" manufactured by many companies. In 1948 the cylindrical Curta calculator, which was compact enough to be held in one hand, was introduced after being developed by Curt Herzstark in 1938. This was an extreme development of the stepped-gear calculating mechanism. It subtracted by adding complements; between the teeth for addition were teeth for subtraction. From the early 1900s through the 1960s, mechanical calculators dominated the desktop computing market. Major suppliers in the USA included Friden,