John Vincent Atanasoff

It is difficult to credit the invention of the first digital computer to any single individual. Although the 1944 ENIAC, designed by J. PRESPER ECKERT and JOHN MAUCHLY, is widely considered to be the first fully functional electronic digital computer, John Vincent Atanasoff and his graduate assistant Clifford Berry created a machine five years earlier that had many of the features of modern computers. Indeed, a court would eventually declare that the Atanasoff-Berry Computer (ABC) was the first true electronic computer.
Atanasoff was born October 4, 1903, in Hamilton, New York. His father was an electrical engineer, his mother a teacher, and both parents encouraged him in his scientific interests. In particular, the young boy was fascinated by his father’s slide rule. He learned about logarithms so he could understand how the slide rule worked. He also showed his father’s aptitude for electrical matters: When he was nine years old, he discovered that some wiring in their house was faulty, and fixed it.
John blazed through high school in only two years, making straight A’s. By then, he had decided to become a theoretical physicist. When he entered the University of Florida, however, he majored in engineering and mathematics because the school lacked a physics major. Offered a number of graduate fellowships, Atanasoff opted for Iowa State College because he liked its programs in physics and engineering. He earned his master’s degree in mathematics in 1926.
Atanasoff continued on to the University of Wisconsin, where he earned his doctorate in physics in 1930. He would remain there as a professor of physics for the next decade. Like HOWARD AIKEN, Atanasoff discovered that modern physics was encountering an increasing burden of calculation that was becoming harder and harder to meet using manual methods, the slide rule, or even the electromechanical calculators being used by business.
One alternative in development at the time was the analog computer, which used the changing relationships between gears, cams, and other mechanical components to represent quantities manipulated in equations. While analog computers such as the differential analyzer built by VANNEVAR BUSH achieved success in tackling some problems, they tended to break down or produce errors because of the very exacting mechanical tolerances and alignments they required. Also, these machines were specialized and hard to adapt to different kinds of problems. Atanasoff made a bold decision. He would build an automatic, digital electronic calculator. Instead of the decimal numbers used by ordinary calculators, he decided to use binary numbers, which could be represented by different amounts of electrical current or charge. The binary logic first developed by GEORGE BOOLE could also be manipulated to perform arithmetic directly. Equally important, at a time when electric motors and switches drove mechanical calculators, Atanasoff decided to design a machine that would be electronic rather than merely electrical. It would use the direct manipulation of electrons in vacuum tubes, which is thousands of times faster than electromechanical switching.
Atanasoff obtained a modest $650 grant from Iowa State and hired Clifford Berry, a talented graduate student, to help him. In December 1939, they introduced a working model of the Atanasoff-Berry Computer (ABC). The machine used vacuum tubes for all logical and arithmetic operations. Numbers were input from punched cards, while the working storage (equivalent to today’s random-access memory, or RAM), consisted of two rotating drums that stored the numbers as electrical charges on tiny capacitors. The ABC, however, was not a truly general purpose computer: It was designed to solve sets of equations by systematically eliminating unknown quantities. Because of problems with the capacitor-charge memory system, Atanasoff and Berry were never able to solve more than five equations at a time. As the United States entered World War II, Atanasoff had to increasingly divide his time between working on the ABC and his duties at the National Ordnance Laboratory in Washington, D.C., where he headed the acoustics division and worked on designing a computer for naval use. Eventually the ABC project petered out, and the machine never became fully operational. After the war, Atanasoff gradually became disillusioned with computing. The mainstream of the new field went in a different direction, toward the general-purpose machines typified by ENIAC, a large vacuum tube computer. In 1950 Atanasoff discovered that Iowa State had dismantled and partly discarded the ABC. He spent the remainder of his career as a consultant and entrepreneur. In 1952, he and his former student David Beecher founded a defense company, Ordnance Engineering Corporation. In 1961, he became a consultant working on industrial automation, and cofounded a company called Cybernetics with his son.
In 1971, however, Atanasoff and the ABC became part of a momentous patent dispute. Mauchly and Eckert had patented many of the fundamental mechanisms of the digital computer on the strength of their 1944 ENIAC machine. Sperry Univac, which now controlled the patents, demanded high licensing fees from other computer companies. A lawyer for one of these rivals, Honeywell, had heard of Atanasoff’s work and decided that he could challenge the Mauchly-Eckert patents. The heart of his case was that in June 1941 Mauchly had stayed at Atanasoff’s home and had been treated to an extensive demonstration of the ABC. Honeywell claimed that Mauchly had obtained the key idea of using vacuum tubes and electronic circuits from Atanasoff. If so, the Atanasoff machine would be “prior art,” and the Mauchly-Eckert patents would be invalid. In 1973, the federal court agreed, declaring that Mauchly and Eckert “did not themselves invent the automatic electronic digital computer, but instead derived that subject matter from one Dr. John Vincent Atanasoff.”
The decision was not appealed. Despite the definitive legal ruling, the controversy among computer experts and historians grew. Defending his work in public for the first time, Atanasoff stressed the importance of the ideas that Mauchly and Eckert had obtained from him, including the use of vacuum tubes and binary logic circuits. Defenders of the ENIAC inventors, however, pointed out that the ABC was a specialized machine that was never a fully working general-purpose computer like ENIAC. While the dispute may never be resolved, it did serve to give Atanasoff belated recognition for his achievements. On October 21, 1983, the University of Iowa held a special conference celebrating Atanasoff’s work, and later built a working replica of the ABC. By the time Atanasoff died in 1995 at the age of 91, he had been honored with many awards, including the Computer Pioneer Medal from the Institute for Electrical and Electronics Engineers in 1984 and the National Medal of Technology in 1990.