World Computer Day: 80 Years of ENIAC

Today is World Computer Day. It is celebrated annually on February 15th, the anniversary of the unveiling of the "Electronic Numerical Integrator and Computer" (ENIAC), and this year it is a very special event. This is because ENIAC was presented to the American public 80 years ago. Before that, work on the freely programmable computer was strictly secret: from 1943 onwards, J. Prosper Eckert and John W. Mauchly, with 50 employees, worked on developing a control computer for the creation of ballistic firing tables for the US Army's Ballistic Research Center, which was to be used at the Aberdeen Proving Ground. By the time ENIAC was completed on time in December 1945, the war was over. The machine subsequently calculated thermonuclear equations for the Los Alamos hydrogen bomb project before it was demonstrated to the world.

For its 80th birthday, there will be a series of events on World Computer Day, of which ENIAC Day at the American Helicopter Museum in Westchester, Pennsylvania, is likely to be the most important. Here, the children of Eckert and Mauchly will perform, and here the daughters of the ENIAC programmers will tell what they achieved. The event is sponsored by the Compuseum, which is calling on computer users worldwide to turn off their computers for one minute at 2:15 PM EST in honor of ENIAC. ENIAC itself ran from 1945 to 1955 as much as possible without shutdowns because its 17,800 vacuum tubes were sensitive. Therefore, efforts were made to keep it running continuously. The last real use of individual parts of its hardware was on its 50th birthday in the presence of then US Vice President Al Gore, who celebrated ENIAC as the "progenitor" of the Internet in his speech. Gore also received an award from the University of Pennsylvania for the term "Information Superhighway," which he popularized.

From a room with control panels to a single chip

The fact that ENIAC could still really compute thirty years ago was thanks to a chip that students at the University of Pennsylvania had developed for its 50th anniversary and which became known as "ENIAC-on-a-Chip." For the current 80th anniversary, one can marvel at the exact opposite in Gilbert, Arizona. Here, the 30-ton colossus, although not functional, was faithfully recreated by 80 neurodivergent students in the gymnasium of the PS Academy. Their smartphones are more powerful than ENIAC.

The history of ENIAC has been told many times, but its first public presentation less so. The US Army's PR department issued a paper describing ENIAC as a "mathematical robot"; the first report appeared on the day of the presentation in the New York Times. Whether solving differential equations interested the audience is not known. The first to recognize the significance of the invention and describe it scientifically was the British mathematician Douglas Rayner Hartree. He had worked on a differential machine during World War II and was sent to the USA as early as 1945 to study ENIAC. Hartree traveled to the public presentation of the computer at the Moore School of Electrical Engineering at the University of Pennsylvania with Alan Turing, John Womersley, and Maurice Wilkes.

His two-part report appeared in "Nature" in 1946 as "The ENIAC, an electronic calculating machine" and "The ENIAC, an electronic computing machine." In the East, computer pioneer Nikolaus J. Lehmann read Hartree's reports and argued that such sensitive cabinets should not be built. He set about developing his D1 desktop calculator. In the West, ballistics expert Heinrich Pösch wrote in "Zeitschrift für angewandte Mathematik und Mechanik" in 1947 about "Eine automatische Rechenmaschine mittels Röhren" (An automatic calculating machine using tubes). At that time, Pösch was an employee of the French institute SEA, which built the first French tube computers.

The "Electronic Brain"

Away from the professional world, the German-speaking public was informed by articles such as the one about the "machine with a brain." In 1950, "Der Spiegel" described the ENIAC machine brain to its readership, which functioned "alarmingly human." "The main work is done by thousands of electronic tubes: one group performs the actual calculation. A second stacks intermediate solutions and commands to the machine. It represents a kind of 'memory,' a storage from which the machine retrieves what is currently needed at the right time."

It gets particularly eerie when the inside of the machine is described: "The inside of an electronic brain resembles the control center of a radio station. On the walls are shelves with thousands of tubes, switches, and indicator lights. Behind them, a spiderweb of wires. In the center of the 'brain box' is a 'will center,' a central control from which numbers go to the machine. Along with the commands of what should be done with them." Thus, this early description of a computer is not so far removed from today's debate about artificial intelligence, when the "will center" supposedly acts independently.

Eckert and Mauchly had no patience for the rumors about "electronic brains." Immediately after ENIAC was completed, they set to work building an improved version of their computer idea. When asked how he evaluated his work on ENIAC, John Presper Eckert replied: "What surprised me most was the fact that nothing like ENIAC existed, even though all the necessary components had been available 10 or even 15 years earlier. ENIAC should have been invented 10 or 15 years earlier, and the real question is why that didn't happen sooner."

(kbe)