ENIAC: the story on HearLore

ENIAC

On the 10th of December 1945, a machine the size of a small room began to hum with a sound that would echo through the rest of the 20th century. This was the Electronic Numerical Integrator and Computer, known to the world as ENIAC, and it was the first electronic general-purpose digital computer to be completed. While other machines existed before it, none combined programmability, electronic speed, and general-purpose calculation into a single device. The U.S. Army had commissioned the project to calculate artillery firing tables for the Ballistic Research Laboratory, but the machine's first real test was not a simple math problem. It was a study of the feasibility of the hydrogen bomb, a task that would define the machine's legacy before it was even officially unveiled. The press dubbed it a "Giant Brain," a moniker that captured the public imagination and signaled the dawn of a new era in computing. The machine weighed more than 30 tons, stood 8 feet tall, and stretched 100 feet long, occupying 1,800 square feet of floor space. It consumed 150 kilowatts of electricity, enough to power a small town, and relied on 18,000 vacuum tubes to perform its calculations. These tubes burned out almost every day, leaving the machine nonfunctional for half of its operational time, yet it managed to perform 5,000 additions or subtractions per second, a speed one thousand times faster than any electro-mechanical machine of the time. The sheer scale of ENIAC was a testament to the urgency of World War II and the desperate need for faster calculations to support the war effort. The machine was a marvel of engineering, but it was also a product of its time, a time when the stakes were life and death, and the margin for error was nonexistent. The completion of ENIAC in 1945 marked a turning point in the history of technology, a moment when the abstract concept of a programmable computer became a tangible reality that could be used to solve real-world problems. The machine was a symbol of human ingenuity, a machine that could think, or at least, calculate with a speed and precision that no human could match. The story of ENIAC is not just a story of technology, but a story of the people who built it, the women who programmed it, and the world that was changed by it.

The Architects of the Electronic Age

The conception of ENIAC began in June 1941, when John Mauchly, a physics professor at Ursinus College, began to wonder if electronics could be applied to mathematics for faster calculations. He partnered with J. Presper Eckert, a research associate at the University of Pennsylvania, to draft an electronic computer that could work at an excellent pace. Mauchly was not an electronics expert, and Eckert was not a mathematician, but together they formed a partnership that would change the world. The U.S. Army Ordnance accepted their plan in August 1942, giving the University of Pennsylvania a six-months research contract for $61,700. The construction contract was signed on the 5th of June 1943, and work on the computer began in secret at the Moore School of Electrical Engineering under the code name "Project PX." Herman Goldstine, who persuaded the Army to fund the project, was put in charge to oversee it for them. The team of design engineers included Robert F. Shaw, Jeffrey Chuan Chu, Thomas Kite Sharpless, Frank Mural, Arthur Burks, Harry Huskey, and Jack Davis. Each of these men played a crucial role in the development of ENIAC, contributing their expertise to the creation of a machine that was unlike anything the world had ever seen. The machine was a large, modular computer, composed of individual panels to perform different functions. Twenty of these modules were accumulators that could not only add and subtract, but hold a ten-digit decimal number in memory. Numbers were passed between these units across several general-purpose buses, and the panels had to send and receive numbers, compute, save the answer, and trigger the next operation, all without any moving parts. The key to its versatility was the ability to branch, allowing it to trigger different operations depending on the sign of a computed result. The machine was a one-of-a-kind design, never repeated, and it lacked some innovations that soon became well-developed, notably the ability to store a program. Eckert and Mauchly started work on a new design, to be later called the EDVAC, which would be both simpler and more powerful. The story of ENIAC is a story of two men who saw the future of computing and worked tirelessly to bring it to life. Their partnership was a testament to the power of collaboration, a reminder that the greatest achievements are often the result of the combined efforts of many individuals working towards a common goal. The machine was a symbol of human ingenuity, a machine that could think, or at least, calculate with a speed and precision that no human could match. The story of ENIAC is not just a story of technology, but a story of the people who built it, the women who programmed it, and the world that was changed by it.

What was the first electronic general-purpose digital computer to be completed?

The Electronic Numerical Integrator and Computer, known as ENIAC, was the first electronic general-purpose digital computer to be completed. It was finished in 1945 and combined programmability, electronic speed, and general-purpose calculation into a single device.

Who designed and built the ENIAC computer?

John Mauchly and J. Presper Eckert designed and built the ENIAC computer. The team of design engineers included Robert F. Shaw, Jeffrey Chuan Chu, Thomas Kite Sharpless, Frank Mural, Arthur Burks, Harry Huskey, and Jack Davis.

Who were the programmers of the ENIAC computer?

Six women were chosen to be the programmers of the ENIAC computer: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas, and Ruth Lichterman. These women were highly trained mathematicians who studied the machine's logic, physical structure, operation, and circuitry.

When was the ENIAC computer officially unveiled to the public?

The completed ENIAC machine was announced to the public the evening of the 14th of February 1946. A press conference was held on the 1st of February 1946, and the machine was formally dedicated the next day at the University of Pennsylvania.

What was the first problem assigned to the ENIAC computer?

The first problem assigned to the ENIAC computer was the hydrogen bomb. In December 1945, the ENIAC was used to calculate thermonuclear reactions using equations to support research on building a hydrogen bomb.

When did the ENIAC computer stop operating?

The ENIAC computer was in continuous operation until 11:45 p.m. on the 2nd of October 1955, when it was retired in favor of the more efficient EDVAC and ORDVAC computers. It was transferred to Aberdeen Proving Ground in Aberdeen, Maryland in 1947.

The Women Who Programmed the Machine

While the men designed the machine, it was the women who brought it to life. Six women were chosen to be the programmers of ENIAC: Kay McNulty, Betty Jennings, Betty Snyder, Marlyn Wescoff, Fran Bilas, and Ruth Lichterman. These women were not "refrigerator ladies," models posing in front of the machine for press photography, but highly trained mathematicians who had been hired to calculate ballistics tables with mechanical desk calculators and a differential analyzer prior to and during the development of ENIAC. The job of computers was to produce the numeric result of mathematical formulas needed for a scientific study, or an engineering project. They usually did so with a mechanical calculator, but the women studied the machine's logic, physical structure, operation, and circuitry in order to not only understand the mathematics of computing, but the machine itself. This was one of the few technical job categories available to women at that time. The women were often able to narrow bugs down to an individual failed tube which could be pointed to for replacement by a technician. They were not "professionals" in the eyes of their contemporaries, who designated them "subprofessionals," even though they had professional degrees in mathematics and were highly trained mathematicians. The labor shortage created by World War II helped enable the entry of women into the field, but the field was not viewed as prestigious, and bringing in women was viewed as a way to free men up for more skilled labor. The women were seen as meeting a need in a temporary crisis, and their contributions were often overlooked. After the war ended, the women continued to work on the ENIAC, and their expertise made their positions difficult to replace with returning soldiers. Later in the 1990s, Kathryn Kleiman learned that most of the ENIAC programmers were not invited to the ENIAC's 50th anniversary event. She made it her mission to track them down and record their oral histories. "They were shocked to be discovered," Kleiman says. "They were thrilled to be recognized, but had mixed impressions about how they felt about being ignored for so long." The women's contributions to the field of computing were finally recognized in 1997, when they were inducted into the Women in Technology International Hall of Fame. Their story is a testament to the power of perseverance, a reminder that the greatest achievements are often the result of the combined efforts of many individuals working towards a common goal. The women who programmed ENIAC were not just technicians, but pioneers who paved the way for future generations of women in computing. Their story is a reminder that the history of technology is not just a story of machines, but a story of the people who built them, the women who programmed them, and the world that was changed by them.

The Public Deception and the Real Story

A press conference was held on the 1st of February 1946, and the completed machine was announced to the public the evening of the 14th of February 1946, featuring demonstrations of its capabilities. Elizabeth Snyder and Betty Jean Jennings were responsible for developing the demonstration trajectory program, although Herman and Adele Goldstine took credit for it. The machine was formally dedicated the next day at the University of Pennsylvania. None of the women involved in programming the machine or creating the demonstration were invited to the formal dedication nor to the celebratory dinner held afterwards. The public demonstration for ENIAC was developed by Snyder and Jennings who created a demo that would calculate the trajectory of a missile in 15 seconds, a task that would have taken several weeks for a human computer. The machine was a symbol of human ingenuity, a machine that could think, or at least, calculate with a speed and precision that no human could match. The story of ENIAC is not just a story of technology, but a story of the people who built it, the women who programmed it, and the world that was changed by it. The machine was a one-of-a-kind design, never repeated, and it lacked some innovations that soon became well-developed, notably the ability to store a program. Eckert and Mauchly started work on a new design, to be later called the EDVAC, which would be both simpler and more powerful. The story of ENIAC is a story of two men who saw the future of computing and worked tirelessly to bring it to life. Their partnership was a testament to the power of collaboration, a reminder that the greatest achievements are often the result of the combined efforts of many individuals working towards a common goal. The machine was a symbol of human ingenuity, a machine that could think, or at least, calculate with a speed and precision that no human could match. The story of ENIAC is not just a story of technology, but a story of the people who built it, the women who programmed it, and the world that was changed by it.