Harvard Mark I

The Harvard Mark I also known as the IBM ASCC, the Automatic Sequence Controlled Calculator was long thought to be the first large scale automatic digital computer, until after World War II the Z3 by Konrad Zuse was discovered.

The Mark I was devised by Howard H. Aiken, created at IBM, shipped to Harvard in February 1944 and formally delivered there on August 7, 1944.

The building elements of the Mark I were switches, relays, rotating shafts, and clutches. It was built using more than 750,000 components, amounting to a size of 50 feet in length, 8 feet in height and a weight of about 5 tons.

The most famous operator / programmer of the Harvard Mark I was Grace Hopper.

Other universities have their "Mark I" computers as well, but the Harvard Mark I is generally described as "the" Mark I.

See Also

• History of computing
• Other early computers:
  • Atanasoff Berry Computer
  • Colossus computer
  • ENIAC
  • Manchester Mark I
  • Z3

External links

• IBMs ASCC Reference Room
• Mark I operational manual