Howard Aiken conceptualized and developed the world’s first large-scale computer. While he was working on his doctoral thesis at Harvard, Aiken had to solve nonlinear differential equations, which were tedious and too complex for calculators to handle. This dilemma gave him the idea to create a calculator that was powerful enough to handle advanced mathematics.

**Mark I**

Together with a small team of engineers, including pioneering computer programmer Grace Hopper, Aiken spent five years designing and building a massive electromechanical computer. It cost $250,000 to build, equivalent to $3.4 million today. The Automatic Sequence Controlled Calculator, nicknamed the Mark I, was unveiled and put to work in 1944.

It was a cumbersome, noisy machine made of nearly 760,000 parts. Hardly resembling today’s sleek touchscreen computers, the Mark I filled an entire room with clicking metal parts. It used prepunched paper tape for input and typewriters for output. Mark I was slow but steady, and stayed in use for a decade. It took between three and six seconds just to add two numbers and it could run continuously for 24 hours a day, seven days a week.

It was clunky, mechanical, and and slow, but Howard Aiken’s innovative early computer paved the way for today’s advanced digital technology. Today a computer of that size would be capable of computing, storing, analyzing and communicating enormous amounts of data much more quickly. For example, Northrop Grumman is developing an Advanced Extremely High Frequency (AEHF) system of satellites with a payload that delivers the new XDR (Extreme Data Rate) communications services with data rates as fast as 8.192 Mbps per user.

**A Remarkable Career**

Creating the Mark I was just the first highlight of Howard Aiken’s rich career. He was an electrical engineer, a mathematician, a physicist, a naval officer and ultimately a computer scientist.

At Harvard, he taught applied mathematics and directed the Harvard Computation Laboratory. He also developed the country’s first master’s and doctoral programs in computer science. He mentored many of the world’s first computer scientists and directed a team that published fundamental research in switching theory, data processing, and computing components and circuits.

During World War II, Aiken and his team used the Mark I for strategic wartime work. They solved top-secret calculations such as computing rocket trajectories, gunnery, ballistics and naval design. His team also designed later versions of the computer that were used for scientific research and military calculations.

**Howard Aiken’s Legacy Continues Today**

When Aiken passed away in 1973, the New York Times published his obituary with the heading, “Howard H. Aiken, Built Computer.” He was quoted as saying, “The only advantage of computers is greatly increased speed. But they can act only on information fed into them. And such information depends on the judgment of executives. Executive decisions may be speeded by its results.” He was speaking during the early age of computers, but his words are more relevant today than ever, with automation in just about every workplace.

The Mark I and Aiken’s complete body of work are the foundation for modern day computing. He gave computer scientists the tools that evolved into today’s vibrant information technology field. Now, with the proliferation of IoT, social media and electronic gadgets, sensors and systems are everywhere so an overwhelming amount of data is available. Aiken’s work — building the machine and painstakingly documenting mathematical tables — gives us the ability to make sense of big data. Aiken couldn’t possibly have imagined the rich and varied ways that his calculating machine and its successors would be used today.