Calculator history

June 1957 - Casio releases the first compact calculator, the Model 14-A.

Oct 1961 - The Bell Punch/Sumlock Comptometer ANITA is released, a 30+ pound calculator using vacuum tubes.

June 1963 - The ANITA is superseded by the full- transistor design of the Friden EC-130.

Late 1965 - The Olivetti Programma 101, considered to be the first personal computer/calculator, is released.

Also late 1965 - The ELKA 6521 designed by Bulgaria is produced; it is the first calculator with a square root function.

1967 - An engineer at Texas Instruments begins work on the first handheld calculator.

Jan 1971 - The Sharp EL-8 is released. It is one of the closest things to a pocket calculator at the time.

Early 1971 - Texas Instruments continues innovation in calculators and works on "calculators on a chip" using integrated circuits (ICs).

Also early 1971 - The first true pocket calculator, the LE-120A "HANDY", is released by Busicom. It is also the first calculator using an LED display, a single IC, and replaceable batteries.

Feb 1972 - HP releases the HP-35, the first scientific pocket calculator for the public.

1976 - 4-function pocket calculators only cost a few dollars.

Throughout 1964 - Various other full-transistor calculators are produced.

1973-1977 - Texas Instruments works on various pocket calculators, starting with the SR-10 and leading up to the TI-30.

1980s & 1990s - HP and TI, the leading calculator manufacturers, compete and 1-up each other constantly with new functions and abilities for their calculators.