9th Century

• The Banū Mūsā brothers invent a digital music player.

1642

• Blaise Pascal invented the digital, mechanical calculator.

1703

• Gottfried Leibniz published Explanation of the Binary Arithmetic

1725

• Basile Bouchon used punched cards to store information. In this case, to control a loom.

1792

• Claude Chappe invented the optical telegraph.

1804

• The Jacquard machine expanded on Bouchon's loom.

1820

• Charles Xavier Thomas improved the calculator.

1832

• Semyon Korsakov used punch cards to store and search information.

1835

• Joseph Henry invented the relay.

1837

• Charles Babbage proposed the Analytical engine.
• Samuel Morse developed Morse code.

1843

• Alexander Bain invented a fax machine.

1854

• George Boole published The Laws of Thought introducing Boolean algebra.

1869

• William Stanley Jevons invented the logical machine. His version was called a logic piano.

1883

• Allan Marquand improved the logical machine.

1886

• Charles Sanders Peirce described how boolean operations could be solved by electrical switches.
• Herman Hollerith invented the tabulating machine.

1895

• Otto Schäffler invented the plugboard.

1904

• John Ambrose Fleming invented the diode (the Fleming valve).

1906

• Lee de Forest invented the triode.

1909

• Percy Ludgate designed a mechanical analytical engine.

1912

• Leonardo Torres Quevedo built El Ajedrecista.

1918

• William Eccles and FW Jordan invented the flip-flop circuit.

1936

• Alan Turing conceived the Turing machine.

1937

• Claude Shannon wrote A Symbolic Analysis of Relay and Switching Circuits which advocated that Boolean logic should be used to design digital logic circuits.
• George Stibitz built the Model K adder.

1938

• Konrad Zuse built a programmable, digital computer- the Z1.

1940

• Edward Condon designed the Nimatron.

1942

• John Atanasoff built a nonprogrammable, digital computer- the ABC.

1943

• Tommy Flowers built the Colossus- an electronic, digital, programmable computer.

1944

• Howard Aiken designed and IBM built the Harvard Mark I- a programmable calculator.

1945

• Eckert and Mauchly built the ENIAC- the first programmable, electronic, general-purpose digital computer.
• John von Neumann described the von Neumann architecture.

1947

• William Shockley invented the transistor.

1948

• Claude Shannon wrote A Mathematical Theory of Communication which proved that all information can be encoded digitally and coined the term, bit.

1956

• Wen Tsing Chow invented PROMs.

1960

• Robert Noyce, one of the traitorous eight, invented the monolithic integrated circuit chip.

1970

• Texas Instruments developed the 74181 ALU.

1971

• Federico Faggin designed the Intel 4004.
• Dov Frohman invented EPROMs.

1975

• Ed Roberts developed the Altair 8800.