Timeline: The 1940s

← Before 1940 · [[index|Thematic index]] · The 1950s →

1940

• Zuse’s Z2 tests telephone relays for arithmetic. → Konrad Zuse and the Z3
• Bush presents Roosevelt with a one-page plan for wartime science mobilization in June. → Vannevar Bush and the Memex
• George Stibitz operates the Complex Number Calculator in New York from a teleprinter at Dartmouth College → George Stibitz and the Complex Number Calculator

1941

• A German operator’s error on 30 August gives Bletchley Park the key stream from which Bill Tutte reconstructs the Lorenz cipher machine. → Tommy Flowers and Colossus
• Helmut Hölzer builds the first fully electronic analog computer at Peenemünde to simulate the A4 rocket. → Helmut Hölzer
• Konrad Zuse presents the Z3 in Berlin on 12 May. → Konrad Zuse and the Z3
• John Mauchly arrives in Ames for four days with Atanasoff and the ABC. → John Atanasoff and the ABC

1942

• Hedy Lamarr and George Antheil patent frequency-hopping spread spectrum. → Hedy Lamarr and Frequency Hopping
• Schreyer’s experimental 100-tube machine exists; his 2,000-tube proposal is rejected. → Helmut Schreyer: The Missed Electronic Age
• The Ballistic Research Laboratory’s firing-table backlog creates the demand for ENIAC. → ENIAC and the First Electronic Computers
• The Daily Telegraph crossword contest staffs Bletchley Park. → Recruiting by Puzzle
• The Mischgerät, Hölzer’s electronic guidance computer, flies on the A4; it is the first computer aboard a vehicle. → Helmut Hölzer

1943

• Curt Herzstark is arrested in Vienna and sent to Buchenwald, where he draws the Curta calculator → Curt Herzstark and the Curta
• McCulloch and Pitts model neurons as logic gates; Wiener and Rosenblueth publish “Behavior, Purpose and Teleology”. → Norbert Wiener and Cybernetics
• NACA establishes the segregated West Area computing pool; Dorothy Vaughan is hired. → Women in Computing: The Invisible Pioneers
• Tommy Flowers builds Colossus at Dollis Hill for Bletchley Park. → Tommy Flowers and Colossus
• Eckert and Mauchly’s ENIAC proposal is presented and approved at Aberdeen on 9 April. → ENIAC and the First Electronic Computers
• The Army signs the ENIAC contract with the Moore School on 5 June. → ENIAC and the First Electronic Computers
• McCulloch and Pitts publish the first mathematical model of a neural network → McCulloch and Pitts

1944

• Grace Hopper is commissioned in the Naval Reserve and assigned to the Harvard Mark I. → Grace Hopper: The Queen of Code
• IBM builds Howard Aiken’s electromechanical Harvard Mark I. → IBM: The Company
• Whirlwind is conceived at MIT as a Navy flight simulator; it becomes the first real-time computer. → Whirlwind, SAGE, and Core Memory
• Colossus Mark 1 arrives at Bletchley Park on 18 January. → Tommy Flowers and Colossus
• IBM’s ASCC is dedicated at Harvard as the Harvard Mark I → Howard Aiken and the Harvard Mark I

1945

• Perry Crawford sees ENIAC and turns Whirlwind digital. → Whirlwind, SAGE, and Core Memory
• Six women are selected to program ENIAC. → Women in Computing: The Invisible Pioneers
• The EDVAC report describes the stored-program architecture. → The Von Neumann Architecture
• Vannevar Bush’s “As We May Think” describes the Memex. → Vannevar Bush and the Memex
• The First Draft of a Report on the EDVAC circulates in the last week of June. → The Von Neumann Architecture
• Von Neumann’s First Draft of a Report on the EDVAC, dated 30 June, spreads the stored-program design. → John von Neumann
• ENIAC runs its first test calculation on 10 November. → ENIAC and the First Electronic Computers
• Alan Turing completes his report Proposed Electronic Calculator for the ACE → Alan Turing and the ACE

1946

• Antonín Svoboda returns from MIT to Prague. → Czechoslovakia’s Computing Industry: Svoboda, SAPO, and the Institute That Lost Its Founder
• Post introduces the correspondence problem, later a standard tool for undecidability proofs. → Emil Post
• RCA begins developing the Selectron memory tube for von Neumann’s IAS computer. → The Memory Race Before Core: Delay Lines, Williams Tubes, and the Selectron
• Sony is founded in postwar Tokyo. → Sony: From Rice Cooker to PlayStation
• The IEEE Computer Society’s institutional origins begin. → IEEE Computer Society
• The Macy Conferences on cybernetics begin. → Norbert Wiener and Cybernetics
• ENIAC is dedicated at the Moore School on 15 February. → ENIAC and the First Electronic Computers
• Wilkes reads the EDVAC report in one night in May and decides to build a stored-program machine. → Maurice Wilkes and EDSAC
• The Moore School Lectures, the first course on building computers, open in Philadelphia on 8 July. → Computer Science Locations

1947

• Bell Labs formalizes the cellular concept of frequency reuse. → Cellular Networks: From 1G to 5G
• George Dantzig invents the simplex method. → George Dantzig and the Simplex Method
• Kathleen Booth creates the first assembly language at Birkbeck. → Kathleen Booth and the First Assembler
• The Haloid Company of Rochester licenses Carlson’s electrophotography from Battelle; the word xerography is coined the next year. → Chester Carlson
• Harvard’s Symposium on Large-Scale Digital Calculating Machinery opens with 336 participants → Howard Aiken and the Harvard Mark I
• A moth is taped into the Harvard Mark II logbook on 9 September: “first actual case of bug being found”. → Grace Hopper: The Queen of Code
• The Association for Computing Machinery is founded on 15 September. → ACM: The Association for Computing Machinery
• Eckert and Mauchly apply for a patent on mercury delay-line memory. → The Memory Race Before Core: Delay Lines, Williams Tubes, and the Selectron
• Bardeen and Brattain demonstrate the point-contact transistor at Bell Labs on 16 December. → The Transistor: The Invention That Made Everything Else Possible
• Eckert and Mauchly incorporate the Eckert-Mauchly Computer Corporation in Philadelphia → UNIVAC and the Eckert-Mauchly Computer Corporation

1948

• Heinz Billing’s first magnetic drum memory, a cylinder wrapped in magnetic tape, runs in Göttingen. → Heinz Billing
• Jean Bartik’s team converts ENIAC to stored-program operation. → Women in Computing: The Invisible Pioneers
• Monte Carlo simulations designed by John and Klára von Neumann run on ENIAC, starting 12 April. → Monte Carlo Methods
• Shannon’s “A Mathematical Theory of Communication” founds information theory. → Claude Shannon and Information Theory
• Shockley invents the junction transistor, the manufacturable form of the device. → From Vacuum Tubes to Transistors: The Dawn of the Semiconductor Age
• Wiener publishes Cybernetics. → Norbert Wiener and Cybernetics
• IBM inaugurates the SSEC next to its New York headquarters on 27 January. → IBM: The Company
• The Manchester Baby runs the first stored program on 21 June. → The Manchester Baby: The First Stored-Program Computer
• Bell Labs announces the transistor at a New York press conference on 30 June. → The Transistor: The Invention That Made Everything Else Possible

1949

• CSIRAC, among the first stored-program computers in the world, runs in Australia. → Australia’s Tech Industry: Atlassian, WiFi, and the Tyranny of Distance
• Donald Hebb proposes his learning rule in The Organization of Behavior → McCulloch and Pitts
• Dorothy Vaughan becomes NACA’s first Black supervisor. → Women in Computing: The Invisible Pioneers
• EDSAC runs at Cambridge, the first stored-program computer to offer a regular service. → Maurice Wilkes and EDSAC
• Edmund Berkeley publishes Giant Brains, or Machines That Think, the first book about computers for general readers. → Edmund Berkeley: Giant Brains and the Social Responsibility of Computing
• Jack Harrington’s group at the Air Force Cambridge Research Center builds a modem to send radar data over phone lines → The Modem and the Carterfone Decision
• The Manchester Mark 1, with the first index registers, is running. → The Manchester Baby: The First Stored-Program Computer
• The Curta pocket calculator from Contina AG, Liechtenstein, is shown at the Basel fair → Curt Herzstark and the Curta
• EDSAC runs its first program, a table of squares, on 6 May. → Maurice Wilkes and EDSAC
• Jay Forrester notes the coincident-current idea for core memory on 13 June. → Whirlwind, SAGE, and Core Memory
• The Soviet atomic test in August turns Whirlwind into an air-defense project. → Whirlwind, SAGE, and Core Memory
• Silver and Woodland file their patent for the barcode on 20 October. → Barcodes and the UPC
• An Wang files his core-memory patent on 21 October. → Whirlwind, SAGE, and Core Memory

Other Timelines

Chronologies kept by the Computer History Museum in Mountain View:

• Timeline of Computer History: people, machines and events across computing, filterable by theme.
• The Silicon Engine: semiconductors from the first documented semiconductor effect in 1833 to the integrated circuit.
• The Storage Engine: data storage from punched cards onward.
• Internet History, 1962 to 1992: the networks that became the internet.
• Apple@50: Apple from its founding in 1976.
• This Day in History: computing events by calendar day.

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