First Computer

There is no single machine that can be called the “first computer”, because the answer depends on how a computer is defined. In the 19th century, Charles Babbage designed the Analytical Engine, a mechanical machine that was intended to perform calculations according to instructions, although it was never completed. In the 1930s and 1940s, several experimental machines brought computing closer to the modern idea.

In 1941, German engineer Konrad Zuse completed the Z3, an automatic programmable machine that used electromechanical relays. During the Second World War, British engineers also developed Colossus, an electronic machine designed for code-breaking. These machines had different purposes and technologies, so historians distinguish between several important “firsts” rather than identifying one universal first computer.

One of the most influential milestones was ENIAC, completed in the United States in 1945 and publicly presented in 1946. It was a large electronic, programmable, general-purpose digital computer designed to perform numerical calculations. Unlike earlier mechanical machines, ENIAC used thousands of vacuum tubes to process information electronically and was vastly faster for many calculations. Programming it, however, required changing connections and settings, so it was not as convenient as modern computers.

The development of machines such as Z3, Colossus and ENIAC helped establish ideas that became central to modern computing: automatic processing, programmable instructions and electronic calculation. Later computers became smaller, more reliable and easier to program, especially after the invention of the transistor and the development of integrated circuits. These advances eventually led from room-sized machines to the personal computers, smartphones and other digital devices used today.