Graphing calculator electrical power line transmission. Casio produced the first commercially available graphing calculator, the fx-7000G, in 1985. Casio's innovations include an icon menu for easy access to functions (1994, FX-7700GE and later), graphing in several colors (1995, CFX-9800G), textbook-like "Natural Display" input and output (2004, FX-82ES/300ES & FX-9860G), expandable memory (2005, FX-9860SD), backlit screen (2006, FX-9860G Slim), full-color, high resolution backlit screen (2010, FX-CG10/CG20 PRIZM). Sharp produced its first graphing calculator, the EL-5200, in 1986. Since then Sharp's innovations include models with a touchscreen (EL9600 series), Equation Editor (textbook-like input) (EL-9300 ( 1992 ) and later), and reversible keyboard to ease
Calculator graph-based calculator for solving line equations involving hyperbolic functions. This allowed electrical engineers to simplify calculations for inductance and capacitance in power transmission lines. The Curta calculator was developed in 1948 and, although costly, became popular for its portability. This purely mechanical hand-held device could do addition, subtraction, multiplication and division. By the early 1970s electronic pocket calculators ended manufacture of mechanical calculators, although the Curta remains a popular collectable item. The first mainframe computers, using firstly vacuum tubes and later transistors in the logic circuits, appeared in the 1940s and 1950s. This technology was to provide a stepping stone