You’ve probably heard the name ENIAC. Or maybe you’re a fan of The Imitation Game and you think Alan Turing’s "Bombe" was the starting line for everything we do today. Honestly, the answer to what counts as the first computer ever made is messy. It depends entirely on how you define "computer." Are we talking about a machine that just crunches numbers? Does it need to be electronic? Or does it need to store a program in its own memory so it can switch from calculating artillery trajectories to playing a primitive game of chess?
Most people think of a computer as a screen and a keyboard. Obviously, that's not where this started. If we go back far enough, the "first" computer was actually a person. That was a job title. But if we’re talking about gears and metal, the Antikythera mechanism usually takes the crown as the world's oldest analog computer. It’s a 2,000-year-old hunk of bronze found in a shipwreck that could predict eclipses with terrifying accuracy. But it wasn't programmable. It did one thing.
To find the real ancestor of your MacBook or smartphone, we have to look at the 1940s. This was a decade of desperate, war-fueled genius where the definition of "first" gets fought over by historians every single day.
The ENIAC and the Great Misconception
If you open a history textbook from twenty years ago, it’ll tell you the ENIAC (Electronic Numerical Integrator and Computer) was the first. Built at the University of Pennsylvania by John Mauchly and J. Presper Eckert, it was a beast. It weighed 30 tons. It took up 1,500 square feet. It used roughly 18,000 vacuum tubes, which are basically lightbulbs that act as switches. When they turned it on, legend says the lights in Philadelphia dimmed.
✨ Don't miss: UFC 3-460-01: Why This Engineering Standard Is Still Saving Military Hospitals
It was fast. Incredibly fast. It could do 5,000 additions per second. For 1945, that was basically sorcery. But ENIAC had a massive flaw that most people overlook. It wasn't "stored-program." If you wanted to change the task ENIAC was doing, you didn't just click a new app. You had to physically reroute hundreds of cables and flip manual switches. It took days. Sometimes weeks. It was more like a giant, electronic calculator that you had to rebuild every time you wanted to do a different math problem.
Also, we can't talk about ENIAC without mentioning the "ENIAC Six." These were the women—Kay McNulty, Betty Jennings, Marlyn Wescoff, Ruth Lichterman, Elizabeth Bilas, and Jean Bartik—who actually did the "programming." Back then, the men built the hardware and thought the wiring was "clerical" work. In reality, these women were the world's first coders, figuring out how to translate complex differential equations into physical cable patches.
Charles Babbage and the Dream of 1837
We have to back up. A lot.
Before vacuum tubes, there was steam. Charles Babbage, a grumpy English polymath, designed the Analytical Engine in the mid-1800s. This is the "first computer" that never actually got finished. If it had been built, it would have been a house-sized contraption of brass gears powered by a steam engine.
Babbage’s design is crucial because it had all the parts of a modern PC:
- An "Arithmetic Logic Unit" (he called it the Mill).
- Memory (the Store).
- Control flow (conditional branching and loops).
Ada Lovelace, the daughter of Lord Byron, saw what Babbage was doing and realized something he didn't. She saw that the machine could manipulate symbols, not just numbers. She wrote what is widely considered the first machine algorithm, making her the first programmer in history. She basically predicted Spotify and Photoshop 150 years before they existed. Babbage died broke, and his machine was never finished, but the logic was sound. He had the blueprint. He just didn't have the manufacturing precision to make it work.
The Z3: Germany’s Secret Success
While the Americans were working on ENIAC, a German engineer named Konrad Zuse was building the Z3 in his parents' living room. This was 1941.
The Z3 was actually the first functional, fully automatic, programmable digital computer. It used 2,000 electromechanical relays. It was binary. It worked. But because it was built in Nazi Germany during World War II, the rest of the world didn't really find out about it until much later. The original was destroyed in an Allied bombing raid in 1943.
Historians argue about this constantly. If the Z3 came first, why do we celebrate ENIAC? Mostly because ENIAC was electronic (using vacuum tubes) while the Z3 was electromechanical (using physical relays). Electronic is faster. Much faster. But in terms of pure logic, Zuse might have beaten everyone to the punch.
Colossus: The Codebreaker
Then there’s the British. At Bletchley Park, Tommy Flowers and a team of engineers built Colossus in 1943.
Its job was specific: crack the Lorenz cipher used by the German High Command. It was the first programmable, electronic, digital computer. So why isn't it the first computer ever made? Because it was a military secret. For decades. The British government broke the machines into pieces after the war and burned the blueprints. It wasn't until the 1970s that the world even knew Colossus existed.
Colossus wasn't "Turing complete," meaning it couldn't solve any problem you gave it—it was designed for codebreaking. But it proved that vacuum tubes could be used for large-scale logic, paved the way for everything else.
The Manchester Baby: The Missing Link
If you want to know what the first computer was that actually looks like how we use computers today, you have to look at the Manchester Baby (the Small-Scale Experimental Machine).
🔗 Read more: Why Everyone Is Buying an AirPods Pro Case Luggage Style This Year
Built in June 1948 at the University of Manchester, this was the first machine to ever run a program stored in its own memory. Before this, programs were on paper tapes or plugboards. The "Baby" was the first time a computer could hold a set of instructions electronically and execute them. It was tiny. It had a memory of only 32 words. But it worked. The moment that first program ran—a simple factoring calculation—the modern era of computing truly began.
Why the Definition Matters
So, who wins?
- The Antikythera Mechanism: First analog computer (ancient Greece).
- The Analytical Engine: First design for a general-purpose computer (1837).
- The Z3: First working programmable digital computer (1941).
- The Colossus: First electronic programmable computer (1943).
- The ENIAC: First high-speed, general-purpose electronic computer (1945).
- The Manchester Baby: First stored-program computer (1948).
It’s a bit like asking who invented the car. Was it the guy who drew a carriage with an engine, or the guy who actually built one that drove down the street?
Expert Insights: The Shift from Hardware to Logic
When you look at these machines, you notice a pattern. In the beginning, "computing" was a hardware problem. If you wanted to do a new calculation, you moved a gear or changed a wire.
The real revolution wasn't just the electricity; it was the Von Neumann Architecture. Named after John von Neumann (though many argue the ideas came from the ENIAC team), this is the concept that the data and the program should be stored in the same place. This is what allows your phone to be a camera one second and a calculator the next. Without this "stored-program" breakthrough, we’d still be rewiring our houses every time we wanted to open a new tab in Chrome.
Practical Takeaways for Tech History Buffs
If you're researching this for a project or just want to be the smartest person in the room during a trivia night, keep these specific points in mind:
💡 You might also like: Why How to Make a Live Photo Loop is Still the Best Way to Share Memories
- Don't ignore the vacuum tubes. The jump from relays (mechanical switches) to vacuum tubes (electronic switches) is what allowed computers to go from "slow human speed" to "lightning speed."
- The "First" is a spectrum. Always ask: "Are we talking about digital, analog, electronic, or stored-program?"
- Software came later. For the first few "computers," software didn't really exist as a separate concept. The machine was the program.
- The Antikythera Mechanism is proof of lost tech. It shows that humans had the logic for computing thousands of years ago, but we lacked the industrial base to keep it going.
To truly understand where we are going with AI and quantum computing, you have to realize that we are still basically using the logic Charles Babbage dreamed up in 1837. We've just made the switches smaller. Instead of 30-ton rooms, we have billions of microscopic transistors etched onto a piece of silicon the size of a fingernail.
How to Explore This History Yourself
If you want to see these beasts in person, there are only a few places that do them justice. The Computer History Museum in Mountain View, California, has parts of the ENIAC and a working reconstruction of Babbage’s Difference Engine. In the UK, the National Museum of Computing at Bletchley Park has a fully functional rebuild of Colossus. Seeing them in person is the only way to realize how loud, hot, and physical these "first" computers really were. They weren't sleek. They were industrial.
The next time your laptop takes five seconds to load a website and you get annoyed, just remember: it took a team of six brilliant mathematicians three days to "wire" a simple multiplication task into the ENIAC. We've come a long way.