Atanasoff, John V.

John Vincent Atanasoff, (born October 4, 1903, Hamilton, New York, U.S.—died June 15, 1995, Frederick, Maryland), American physicist who with his graduate student Clifford Berry developed the Atanasoff-Berry Computer (ABC; 1937–42), a machine capable of solving differential equations using binary arithmetic and one of the first electronic digital computers.

Atanasoff received a bachelor’s degree in electrical engineering from the University of Florida in 1925 and a master’s degree in mathematics from Iowa State College (later Iowa State University) in 1926. He received a Ph.D. in physics from the University of Wisconsin in 1930, and, that same year, he became a professor of physics and mathematics at Iowa State College.

In the mid-1930s Atanasoff became interested in solving partial differential equations with computers but felt that analog machines like the differential analyzer were limited in their applications. The computer he designed had capacitors to store data in binary form and electronic logic circuits to perform addition and subtraction. He and Berry built a small prototype computer in 1939 and worked until 1942 on the full-scale version, the ABC (which Atanasoff named in 1968 after Berry’s death).

In 1942 Atanasoff joined the Naval Ordnance Laboratory; he participated in the atomic bomb tests at Bikini Atoll (1946). In 1952 he established the Ordnance Engineering Corporation, which he sold in 1956 to Aerojet General Corporation.

Atanasoff was interested in patenting the ABC, but Iowa State College never applied for such a patent. In 1964 J. Presper Eckert, Jr., and John Mauchly patented the electronic digital computer ENIAC (Electronic Numerical Integrator and Computer), which they had completed in 1946. The Sperry-Rand Corporation acquired the ENIAC patent, and in 1967 Honeywell sued Sperry-Rand to break the patent on the basis that the ABC was developed before ENIAC. Mauchly had visited Atanasoff in 1941, had extensive discussions with Atanasoff and Berry about the ABC, and witnessed the ABC in operation. Atanasoff spent nine days in 1971 testifying about the ABC and Mauchly’s visit. In 1973 Judge Earl Larson voided the ENIAC patent on the grounds that the ABC was the first electronic digital computer and that Mauchly had not considered such a device until his time with Atanasoff.