Replica of Atanasoff computer at Iowa State (Wikipedia)

Replica of Atanasoff computer at Iowa State (Wikipedia)

John Vincent Atanasoff

OCTOBER 4, 2018

Scientist of the Day - John Vincent Atanasoff

John Vincent Atanasoff, an American computer scientist born to Bulgarian immigrants, was born Oct. 4, 1903. Atanasoff was in fact the first computer scientist, since he and a student, Clifford Berry, built a digital computer at Iowa State in the late 1930s. It was not programmable, and although it was designed to solve simultaneous linear equations, they didn't really put it to use.  But it had most of the features of a modern digital computer, including a refreshable memory (made, interestingly, of capacitors arranged around a drum). Atanasoff, however, was pulled into other projects during World War II and never patented his invention.

In 1946, John Mauchly and Pres Eckert unveiled their own digital computer, called ENIAC, which was programmable and which was actually used, for computing projectile ballistics and then for designing the hydrogen bomb. They were finally awarded a patent in 1964. It turns out that Mauchly had seen Atanasoff's computer in 1941 and had spent considerable time discussing computing prospects with Atanasoff.  Atanasoff never complained about not receiving any credit (or a share of the patent). But Honeywell Corporation complained; they were trying to build computers of their own in the early 1970s, but Sperry Rand now held all the patents for ENIAC, and they sued Honeywell for patent infringement. Honeywell counter-sued, maintaining that the patent was invalid.

On Oct. 19, 1973, the judge ruled against Sperry Rand, and one of the surprising findings was this one, point 3.1.2 of the 248 page decision: "Eckert and Mauchly did not themselves invent the automatic electronic computer, but instead derived that subject matter from one Dr. John Vincent Atanasoff. The court had declared Atanasoff the inventor of the digital computer, much to Atanasoff’s surprise! It took him a while to become famous--the day after the decision, Richard Nixon fired special prosecutor Archibald Cox in the “Saturday Night Massacre” and stole all the headlines for weeks--but Atanasoff is famous now, especially in Bulgaria, where half the buildings in Sofia seem to be named after him. Eckert and Mauchly still have their defenders, and that is OK, since ENIAC had many features that Atanasoff’s computer lacked, so it appears that the answer to the question, “who invented the digital computer?” will be a subject of  debate for some time to come.

Atanasoff’s computer was broken up in the 1940s, and although some photos survive (third and fourth images), we don’t really know its exact details.  Nevertheless, and understandably, Iowa State has built a replica, which you can see at the Durham Center for Computing on the Ames campus (first image).  It is often referred to as the Atanasoff-Berry Computer, probably because of the resulting acronym: ABC.

Dr. William B. Ashworth, Jr., Consultant for the History of Science, Linda Hall Library and Associate Professor, Department of History, University of Missouri-Kansas City. Comments or corrections are welcome; please direct to