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Harvard Mark I

Early Computer

An electromechanical computer conceived by Howard Aiken and built by IBM engineers, including Clair Lake and Frank Hamilton, at IBM's Endicott plant, shipped to Harvard in February 1944 and officially presented on 7 August 1944. Grace Hopper was one of its first programmers. Aiken's own press release named himself as sole inventor and credited only one IBM engineer, an omission that visibly angered IBM chairman Thomas Watson, who nearly skipped the dedication ceremony over it; the credit for the machine has been contested between Aiken and IBM's own engineering team ever since. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/

Facts
Disputed
Significance
Credited to Aiken alone in his own contemporary publicity, though IBM engineers did much of the detailed design and construction; a documented dispute over invention credit rather than a settled attribution. 1
Aiken issued a press release naming himself sole inventor and crediting only IBM engineer James Bryce; IBM chairman Thomas Watson's anger at the omission of the rest of IBM's engineering team is separately documented.
Status
Status
Discontinued 1
Year
1944 1
FAQs

How fast was the Harvard Mark I and what became of it?

It took three seconds to do one multiplication and was retired in 1959.

The Harvard Mark I took three seconds to carry out one multiplication. It could store 72 numbers, each of 23 decimal digits, and it was used only for numeric calculations, reading its instructions from one paper tape and its data from another. It was retired in 1959 and disassembled, and parts of it are archived at Harvard in the Science Center.
Connections

Associated With

Grace Hopper, Pioneers
Source Wikipedia: Harvard Mark I

In Field

Computer Architecture, Fields
Source Wikipedia: Harvard Mark I

Invented By

Howard Aiken, Pioneers
Source Wikipedia: Harvard Mark I

Long-Form Articles

How the Harvard Mark I ran a program from paper tape, Articles
In the Other Atlases

Developed By

IBM

Also in Business Atlas: the developer of this subject.

Sources
1. Wikipedia: Harvard Mark I
Wikimedia Foundation
  • Aiken and IBM
    Aiken published a press release announcing the Mark I listing himself as the sole inventor.
  • Lead sentence
    Harvard Mark I, or IBM Automatic Sequence Controlled Calculator (ASCC), was one of the earliest general-purpose electromechanical computers used in the war effort during the last part of World War II. One of the first programs to run on the Mark I was initiate
  • In Field: Computer Architecture, Lead section
  • Associated With: Grace Hopper, Legacy section
    the first programmers of the Mark I
  • Invented By: Howard Aiken, Origins section
    the origins of the Harvard Mark I can be traced back to 1935, when Howard Aiken conceived of building a powerful, large-scale calculating machine
  • In Group: Harvard Mark Computers, Lead
    The Harvard Mark I, or IBM Automatic Sequence Controlled Calculator (ASCC), was one of the earliest general-purpose electromechanical computers used in the war effort during the last part of World War II. One of the first programs to run on the Mark I was initiated on 29 March 1944 by John von Neumann.
View the Source
Wikidata: Harvard Mark I
Wikidata Q776823, class allow-list match (w-wdresolver-0926)View the Source
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