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John Atanasoff

John Atanasoff

John Atanasoff (1903-1995) was a pioneer in the field of computer science. In the late 1930s, while teaching at Iowa State University, he designed and built an electronic computing machine with one of his graduate students, Clifford Berry. The Atanasoff-Berry Computer (ABC) was probably the first machine to use vacuum tubes to perform its calculations.

John Vincent Atanasoff was born on October 4, 1903, in Hamilton, New York. He was the son of Ivan (John) Atanasoff, a Bulgarian immigrant who worked as a mining engineer, and an American mother, who taught school. Atanasoff became interested in calculating devices at an early age—he began studying his father's slide rule when he was only nine, and read technical books on mathematics, physics, and chemistry. He decided to be a theoretical physicist while in high school, and went on to the University of Florida, obtaining a degree in electrical engineering. He then received a graduate assistantship at Iowa State College (now Iowa State University), earning a master's degree in mathematics, with a minor in physics, in 1929. Atanasoff completed his doctoral work at the University of Wisconsin, and received his Ph.D. in 1930. He then returned to Iowa State to teach both physics and mathematics.

Constructed a Calculating Machine

Atanasoff's interest in building a calculating machine arose from his need to solve partial differential equations without doing the number crunching by hand, a very slow method. He decided that his machine would have to use base two, in which the only two digits are zero and one, a convention that may be represented electronically in a number of different ways. In particular, the machine that Atanasoff and Berry built did arithmetic electronically, using vacuum tubes to perform the arithmetic operations and capacitors to store the numbers. Numbers were input with punched cards. The primary innovation was that numbers in the computer were digital, and not analog, in nature. The difference between an analog computer—several working versions of which existed at the time—and a digital one is that an analog machine stores its data in terms of position, such as the exact degree of rotation of a numbered wheel, but a digital computer stores its data as a series of binary digits, the zeros and ones of base two. Atanasoff claims to have originated the term "analog" in this application.

The Atanasoff-Berry Computer (ABC) was never expanded or used other than as a calculator. Although Atanasoff and Berry had plans to create a larger machine using the ABC as a building block, those plans were set aside because of World War II, and were never resumed. During the war, Atanasoff worked at the Naval Ordnance Laboratory in Maryland. His only connection with computers at this time occurred when the Navy needed a computer and asked Atanasoff to construct it. Eventually, however, the Navy gave up on the project. Atanasoff then left the computer field. In 1952, he started a firm of his own, Ordnance Engineering Corp., in Frederick, Maryland. Four years later, his firm was sold to Aerojet General Corp. Atanasoff became the firm's vice president and manager of its Atlantic division. He retired from Aerojet in 1961 to become a consultant in package handling automation. Atanasoff then founded another company, Cybernetics, Inc., which his son oversaw.

Won Sperry Rand-Honeywell Suit

Atanasoff became involved with computers again in 1971 when a suit was filed by Sperry Rand, which held a patent for the Electronic Numerical Integrator and Computer (ENIAC) built during the War. The suit alleged that Honeywell had violated the ENIAC patent by not paying Sperry Rand royalties. Honeywell filed a counter-suit charging, among other things, that the inventors of the ENIAC machine were not the inventors of the electronic computer but that Atanasoff was. If accepted by the court, this fact would render the ENIAC patent invalid. The judge handed down his decision on October 19, 1973, finding for Honeywell and also specifically ruling that Atanasoff was the inventor of the electronic computer.

This decision touched off a great deal of controversy. Many people believe that Atanasoff did not really invent the computer but that he was responsible for designing and building a number of early computer components (such as a memory drum). It is recognized that Atanasoff did make significant contributions to the development of the electronic computer despite the fact that he never built a general-purpose computing machine. After his retirement, Atanasoff worked on a variety of projects. Among his completed inventions is a phonetic alphabet for computers. He died on June 15, 1995, in Frederick, Maryland. Atanasoff's honors include, five honorary doctoral degrees, the Navy's Distinguished Civilian Service Award, the Computer Pioneer Medal of the Institute of Electrical and Electronic Engineers, and the Holley Medal of the American Society of Mechanical Engineers. Other honors included the Distinguished Citation of Iowa State University, membership in the Iowa Inventors' Hall of Fame, membership in the Bulgarian Academy of Science, and Bulgaria's highest science award. In 1990, he received the National Medal of Technology from President George Bush.

Further Reading

Shurkin, James, Engines of the Mind: A History of the Computer, W. W. Norton, 1984.

Slater, Robert, Portraits in Silicon, MIT Press, 1987.

New York Times, June 17, 1995, p. A11.

Washington Post, June 19, 1995, p. B4. □

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