Chronology of the History of Computers

3000 B.C. The abacus is developed in Babylonia.


A.D. 700-900 Europeans begin using Hindu-Arabic math.


1600 Hindu-Arabic math is in common use throughout Europe.


1614 John Napier introduces logarithms.


1617 Napier invents rods.


1623 Wilhelm Schickard invents the mechanical calculator.


1630-1633 William Oughtred and Richard Delamain introduce the slide rule.


1644-1645 Blaise Pascal completes his calculator.


1672-1674 Leibniz builds his first calculator.


1801 Joseph-Marie Jacquard develops a loom programmed by punched



1820 The Arithmometer, the first commercial calculator, is introduced.

1823 Charles Babbage begins the Difference Engine project.


1834 Babbage starts designing the Analytical Engine.


1847 George Boole publishes The Mathematical Analysis of Logic.


1853 Pehr and Edvard Scheutz complete their Tabulating Machine.


1854 Boole publishes The Laws of Thought.


1875 Frank Baldwin opens a workshop in Philadelphia, inaugurating the American calculator industry.


1876-1878 Baron Kelvin builds his harmonic analyzer and tide predictor machines.


1878 Ramon Verea patents a calculator capable of direct multiplication and division.


1885 Doff Felt devises the Comptometer, a key-driven adding and subtracting calculator.


1889 Felt’s Comptograph, containing a built-in printer, is introduced.


1890 Herman Hollerith’s punch cards and tabulating equipment are used in the U.S. Census.


1892 William S. Burroughs introduces an adder-subtracter with a superior printer.


1893 The Millionaire, the first efficient four-function calculator, is invented.


1900-1910 Mechanical calculators become commonplace.


1906 Lee De Forest devises a three-electrode tube, or triode.


1910-1913 Bertrand Russell and Alfred North Whitehead publish Principia Mathematica.


1911 Hollerith Tabulating Machine Company merges into Computing- Tabulating-Recording Corporation (CTR).


1914 Thomas Watson, Sr., joins CTR.


1919 W. H. Eccles and F. W. Jordan publish a paper on flip-flop circuits.


1924 CTR becomes International Business Machines Corporation (IBM).


1930 Vannevar Bush completes his differential analyzer, stimulating international interest in analog computing.


1937 Alan Turing publishes “On Computable Numbers.”


1938 Konrad Zuse finishes his Z1, the first binary calculating machine.

Claude Shannon publishes “A Symbolic Analysis of Relay and Switching Circuits.”


1939 Bell Labs builds the Complex Number Calculator.


1941 Zuse assembles the Z3, the first electromechanical general purpose program-controlled calculator.


1942 John V. Atanasoff and Clifford Berry’s electronic calculating machine, one of the first calculating devices with tubes, goes into operation.


1943 IBM-Harvard Mark I is completed.

First Colossus code-breaking machine is installed at Bletchley Park.


1944 J. Presper Eckert and John W. Mauchly conceive of the stored program computer.


1945 ENIAC, the first fully functional electronic calculator, goes into operation in November.

John von Neumann writes “First Draft of Report on the EDVAC.”

IBM becomes the largest business machine manufacturer in the United States.


1946 Arthur Burks, Herman Goldstine, and von Neumann write “Preliminary Discussion of the Logical Design of an Electronic Computing Instrument.”

Von Neumann starts a computer project at the Institute for Advanced Study.

Eckert and Mauchly establish the Electronic Control Company, America’s first computer manufacturer.


1947 Bell Labs invents the point-contact transistor.


1948 IBM assembles the SSEC electromechanical computer, which runs a stored program on 27 January.

Manchester University’s Mark I prototype runs the first fully electronic stored program on 21 June.


1949 EDSAC, the first full-scale electronic stored-program computer, begins operating at Cambridge University in June.

BINAC, the first stored-program computer in America, is tested in August.


1950 Remington Rand buys the Eckert-Mauchly Computer Corporation.


1951 The Ferranti Mark I, the first commercially manufactured computer, is installed at Manchester University in February.

The first UNIVAC is delivered to the Census Bureau in March.

Whirlwind, the first real-time computer, is completed.

William Shockley invents the junction transistor.

Grace Hopper conceives of an internal program known as a compiler.


1952 Thomas Watson, Jr., becomes president of IBM.

UNIVAC successfully predicts the outcome of the presidential election.


1953 IBM delivers the 701, its first electronic computer, to Los Alamos in March.

MIT conducts a successful full-scale test of Jay W. Forrester’s magnetic-core memory.


1954 IBM introduces the 650 medium-size computer in December.


1955 Remington Rand merges with Sperry Corp., forming Sperry Rand.

Shockley establishes a semiconductor company in Mountain View, California.


1956 John McCarthy, an MIT computer scientist, coins the phrase “artificial intelligence. ”


1957 IBM introduces FORTRAN, the first high-level computer language.

Philco Corporation introduces the Philco 2000, the first commercially available transistorized computer.


1958 The first SAGE direction center goes into operation at McGuire Air Force Base in New Jersey.

Jack Kilby builds an integrated circuit (IC) at Texas Instruments in Dallas.

Jean Hoerni devises the planar process for making transistors.


1959 Kurt Lehovec designs an IC whose components are isolated with pn junctions.

Robert Noyce invents a planar IC, paving the way for the mass manufacture of reliable and efficient ICs.


1961 MIT develops the first computer time-sharing system.

Texas Instruments builds the first IC computer.


1963 The Digital Equipment Corporation introduces the minicomputer.

The Bell Punch Company, a British firm, offers electronic calculators using discrete components.


1964 IBM unveils the System/360, the first family of computers.


1968 Noyce and Gordon Moore establish Intel in Santa Clara, California.

Intel introduces the first 1K random-access memory (RAM).


1971 Intel invents the microprocessor.

Mass-produced pocket calculators are introduced in the U.S.


1973 The ENIAC patent is invalidated.

IC computers become commonplace.


1974 An article describing the construction of a “personal minicomputer” appears in Radio-Electronics.


1975 The Altair computer premieres in Popular Electronics, inaugurating the personal computer industry.


1977 The Apple II is introduced.


1981 IBM enters the personal computer market with the PC.


1984 IBM develops a one-million bit RAM.