If you look at most history books, they’ll tell you ENIAC was the first true all-purpose electronic computer. Unveiled in 1946 in a blaze of publicity, it was a monstrous 30-ton machine, as big as two semis and filled with enough vacuum tubes , switches and blinking lights to require an army of attendants. Capable of adding 5,000 numbers in a second, a then unheard of feat, it could compute the trajectory of an artillery shell well before it landed . But while this electronic brain, as headline writers called it, took the spotlight, ENIAC had a lot of unsung rivals, many of them shrouded in wartime secrecy. At Bletchley Park, Alan Turing built a succession of vacuum-tube machines called Colossus that made mincemeat of Hitler’s Enigma codes. At Harvard, large, clattering electromechanical computers in IBM’s Mark series also did wartime calculations. Even the Germans made a stab at computing with Konrad Zuse’s Z electromechanical computers, the last of which was the first general-purpose computer controlled by a program. For years, ENIAC’s principal creators, the late John Mauchly and J. Presper Eckert, held the unchallenged title of inventors of the modern computer–until an obscure physicist named John Atanasoff came forth to dispute their claims. In the late 1930s, while teaching at Iowa State College, he and a graduate student named Clifford Bell began building a device that would allow them to solve large linear algebraic equations. Their machine, later called ABC , incorporated a number of novel features, including the separation of data processing from memory, and relied on binary numbers instead of ENIAC’s clumsier decimal arithmetic. But Atanasoff was called away in 1942 to work for the Navy. Iowa State never filed for patents, and ABC was left abandoned in a storeroom. But not entirely forgotten. In the late 1960s, Sperry Rand, which held the rights to Eckert and Mauchly’s original UNIVAC patents, sued Honeywell for royalty payments. At one point in the six-year litigation, Atanasoff testified that Mauchly cribbed ABC’s key features during a five-day visit in 1941. Mauchly indignantly denied the accusation. But the judge took a different view. In a 1973 decision that was never appealed, he invalidated Eckert and Mauchly’s patents and in effect declared Atanasoff the winner. Historians, however, interpret the ruling more broadly, viewing it as an effort to keep competition alive in a fast-growing industry. So who did invent the computer? Novel as it may have been, ABC could not be reprogrammed, did not handle large numbers well and never became fully operational. By contrast, the reprogrammable ENIAC did initial calculations for the H-bomb, kept flashing away for nearly a decade and led to a host of more sophisticated successors. Take your pick. –By Frederic Golden
