Atanasoff-Berry Computer
In the winter of 1937, John Vincent Atanasoff, a physicist and mathematician at Iowa State University, was driving home on a freezing night. During this journey, his mind suddenly lit up with an insight that would transform the world: four fundamental principles that would form the conceptual foundation of the first electronic computer. These principles were the use of electronics for calculations, the adoption of the binary system, the separation of computation from memory, and the periodic refresh of data in memory.
Born in 1903 in Hamilton, New York, Atanasoff had studied electrical engineering in Florida before turning to mathematics at Iowa State College. His doctorate in theoretical physics from MIT, completed in 1930, had confronted him with the limitations of existing mechanical calculators. These obsolete machines hindered his research on the dielectric constant of helium, a problem requiring computing power that did not yet exist.
The meeting with Clifford Berry changed everything. This brilliant young electrical engineering student brought the technical skills necessary to implement Atanasoff’s ideas. Their collaboration began in 1939 with a rudimentary prototype that validated the basic concepts. This initial success earned them a modest grant of $850 to build the complete machine, the Atanasoff-Berry Computer (ABC).
This machine weighed over 300 kg and featured various innovative elements. Rotating drums covered with capacitors stored data in binary form. Vacuum tubes executed logical operations. Punched cards handled data input and output. A central clock synchronized the entire system. Unlike other calculators, the ABC did not process numbers directly but converted them to binary, a precursor to all modern computers. Its specific purpose was to solve systems of linear equations with up to 29 equations and 29 unknowns, with a remarkable precision of fifteen decimal places.
The fate of this machine took a tragic turn. Completed in 1942, the ABC was abandoned when its creators left the university to contribute to the war effort. The machine suffered from reliability issues, particularly with the punched card system. The university neglected to finalize the patent procedure initiated by Atanasoff. These unfortunate circumstances led to the dismantling of the ABC in 1948, without its contribution to computing being recognized.
The injustice deepened with the appearance of ENIAC in 1945. This machine designed by Presper Eckert and John Mauchly at the University of Pennsylvania was long celebrated as the first electronic computer. The reality was quite different. Mauchly had visited Atanasoff at Iowa State in June 1941, examined the ABC in detail, and read the 35-page manuscript describing its architecture. Many fundamental concepts from the ABC found their way into ENIAC, without attribution to their true creator. Mauchly’s media savvy and generous military funding did the rest: ENIAC stole the spotlight, Atanasoff fell into obscurity.
The truth came to light during a landmark trial. In the 1960s, Honeywell challenged the validity of the ENIAC patent held by Sperry Rand. The legal battle, which lasted from 1971 to 1973, exposed Mauchly’s appropriation of Atanasoff’s ideas. The judge ruled unambiguously: Eckert and Mauchly had not invented the electronic digital computer but had drawn inspiration from Atanasoff’s work. The patent was invalidated, placing the invention of the computer in the public domain.
Official recognition finally came for Atanasoff. In the following decades, he received multiple distinctions, including the prestigious National Medal of Technology presented by President George H. W. Bush in 1990. Books, a biography by Clark Mollenhoff in 1988, and a documentary (Atanasoff: Forgotten Father of the Computer, 2012) were dedicated to him. An exact replica of the ABC was built in the 1990s and displayed at Iowa State University, alongside a rare original memory drum.
Atanasoff’s story illustrates how solitary genius can transform a discipline. By radically questioning existing approaches, he laid the conceptual foundations for all twentieth-century computing. Some of his concepts, such as the use of electronics or binary, became established with ENIAC and later EDVAC. Others, like the stored program, took longer to become industry standards. The ABC played a catalytic role in the evolution of electronic computing, fully justifying Atanasoff’s title as the father of modern computing.