The Mark I Computer at Harvard (2014)

Presentation Date: 

Wednesday, February 12, 2014


Science Center, Harvard University, Cambridge, MA

Originally called the Automatic Sequence Controlled Calculator, Mark I was designed in 1937 by a Harvard graduate student, Howard H. Aiken to solve advanced mathematical physics problems encountered in his research. Aiken’s ambitious proposal envisioned the use of modified, commercially-available technologies coordinated by a central control system. Supported by Harvard faculty in the division that is today the School of Engineering and Applied Sciences, Aiken discussed his idea with several manufacturers, eventually finding interest at IBM, a company that specialized in calculating machines and punch card systems. Using company components, IBM engineers in Endicott, NY developed the machine’s working systems and directed its construction over five years. During that period America entered World War II. When Mark I was finally delivered to Harvard in 1944, it was operated by the U.S. Navy Bureau of Ships for military purposes, solving mathematical problems that until then required large teams of human “computers.”

In the spring of 2014, seventy years after Mark I's arrival at Harvard, a renovation of the permanent exhibit reinterpreted the machine's significance from a 21st century perspective.  Special attention was paid to the crew, which included Grace Hopper, the futuristic look of the Mark I, and how the physical characteristics of the Mark I and its encoded paper tapes gave rise to common programming terms such as the loop, the patch, the library, and the bug.

Co-curated with graduate students Juan Andres Leon and Laura Neuhaus.

Online version of the Mark I exhibition

Detail of Mark I exhibit Mark I at night, 1944 Original Mark I Crew, 1944

See also: 2010s