Atanasoff–Berry computer

A long time ago, men built a machine.

It could do math very fast. It used small glass tubes to work. This helped it work faster than old machines.

The machine was about the size of a desk. It used a special way to remember things. This helped it solve hard math problems. It was a very important early computer. It was built in a school basement.

In 1937, a teacher named John Atanasoff had a big idea.

He worked at Iowa State College. He built a machine with a student named Clifford Berry. They called it the Atanasoff–Berry computer, or ABC.

The ABC was the first electronic digital computer. This means it used electricity to do math. It used vacuum tubes to do its work. These are small glass tubes. Before this, machines used slower mechanical parts. The vacuum tubes made the ABC much faster.

The machine was about the size of a desk. It was made to solve math problems called linear equations. It used a special way to remember data. It used parts called capacitors to store numbers. These were on two large drums that spun around.

For a long time, people thought a machine called ENIAC was the first. But a court ruled in 1973 that ENIAC used ideas from the ABC. The ABC was a very important step for all modern computers.

Today, we can even see displays that honor its history.

The Atanasoff–Berry computer, known as the ABC, was a very special machine. It was the first automatic electronic digital computer ever made.

Most people today use computers for many different tasks. However, the ABC had a very specific job to do. It was built to solve systems of linear equations. These are math problems that scientists in physics often need to solve. Even though it was not a general machine, it changed how we think about technology. It was a huge step toward the computers we use every day.

This machine worked in a very clever way. It used vacuum tubes to perform math calculations. A vacuum tube is a small glass part that uses electricity to switch signals. Before the ABC, other machines used slower mechanical parts like wheels or relays.

The ABC also used a special way to remember information. It used something called regenerative capacitor memory. This memory used two large drums that spun once every second. Each drum had 1,600 capacitors to hold data. This allowed the machine to work much faster than older tools.

An interesting story began in the winter of 1937. A math professor named John Vincent Atanasoff had a sudden insight. He had a long nighttime drive to Rock Island, Illinois. After that drive, he conceived the key ideas for the machine. He worked at Iowa State College with a student named Clifford Berry.

They built the machine in a basement from 1939 to 1942. They used a grant of $5,000 from the Research Corporation of New York City to help them.

There are many important facts about the ABC's design. The machine was about the size of a desk. It used about 280 dual-triode vacuum tubes and 31 thyratrons.

It could perform 30 additions or subtractions every single second. The machine was not programmable, which means you could not give it new instructions easily. It also used binary arithmetic, which means it used a system of ones and zeros. This was a very new way to handle math at that time.

For a long time, people did not know how important the ABC really was. Many thought a machine called ENIAC was the first electronic computer. However, a U.S. District Court looked at the facts in 1973. The court ruled that the ENIAC designers had used ideas from Atanasoff. This helped people rediscover the true history of the ABC. In 1990, the ABC was named an IEEE Milestone to honor its work. Today, you can even see displays in Iowa that celebrate this amazing invention.

The Atanasoff–Berry computer, or ABC, was the first automatic electronic digital computer. It was a groundbreaking machine that changed how we use electricity for math. While modern computers can do almost anything, the ABC was a special-purpose machine. It was designed specifically to solve systems of linear equations. These complex math problems were very important for physics research. The ABC is considered a major milestone because it introduced several ideas we still use. These include binary arithmetic and electronic switching.

To understand how the ABC worked, we must look at its unique components. It used vacuum tubes to perform arithmetic calculations. A vacuum tube is an electronic device that controls the flow of electricity. Before the ABC, machines used slower mechanical parts like wheels or telephone relays. By using tubes, the ABC could calculate much faster than its predecessors. The machine also featured a specialized arithmetic logic unit, or ALU. This part of the computer performed the actual math operations. The ALU operated on one bit of each number at a time. It even kept the carry or borrow bit in a capacitor for the next cycle.

Memory was another vital part of the ABC's design. It used a system called regenerative capacitor memory. This memory consisted of two large drums that rotated on a single shaft. Each drum contained 1,600 capacitors to store data. These drums rotated once every second. The capacitors were organized into 32 bands, with 30 bands being active. Two extra bands were kept as spares in case a capacitor failed. This setup allowed the machine to perform 30 additions or subtractions per second. The electronics could store and operate on 60 numbers at once.

The history of the ABC began with a sudden moment of inspiration. In the winter of 1937–38, Professor John Vincent Atanasoff had a breakthrough. This happened after a long nighttime drive to Rock Island, Illinois. He worked at Iowa State College to bring his ideas to life. He was joined by a graduate student named Clifford Berry. They built the machine in a basement between 1939 and 1942. To fund the project, they received $5,000 from the Research Corporation of New York City. The machine was successfully tested in 1942.

Despite its brilliance, the ABC had several technical limits. It was not a programmable machine. This means it could not follow a new set of instructions for different tasks. It also lacked a stored-program architecture. This type of architecture was not implemented until the Manchester Baby in 1948. The machine also required a human operator to manage its functions. An operator used front-panel switches and jumpers to set up the work. The machine also used a paper card reader for input. For intermediate results, it used a paper card writer. This system was not perfect and had an error rate of about one in 100,000 calculations.

The ABC's legacy was hidden for many years due to legal battles. For a long time, many believed the ENIAC was the first electronic computer. The ENIAC was created by John Mauchly and J. Presper Eckert. However, a major patent dispute changed this understanding. In 1973, a U.S. District Court ruled on the case of Honeywell v. Sperry Rand. The court invalidated the ENIAC patent. The judge concluded that the ENIAC designers had derived their ideas from Atanasoff. This legal decision helped the world rediscover the importance of the ABC.

Today, we recognize the ABC as a foundational piece of technology. In 1990, it was officially designated an IEEE Milestone. While the original machine was dismantled in 1948, its impact remains. Researchers even built a working replica of the ABC in the late 1990s. This replica cost $350,000 to complete. You can still see honors for this invention in Iowa today. The ABC connects the era of mechanical calculators to the era of modern digital computing. It proved that vacuum tubes could make math incredibly fast.