Ada Lovelace

Ada Lovelace was an English mathematician who lived from 1815 to 1852. She is famous for writing what many people call the first computer program. She did this more than a century before any real computer existed. Today she is honored as a founder of computer science.

Ada was born in London. Her father was the famous poet Lord Byron, but he left the family when Ada was just a baby. Her mother, Annabella, worried that Ada might grow up to be a wild dreamer like her father. So she made sure Ada studied lots of math and science. At the time, most girls from rich families learned music and art instead. Ada was lucky to have private tutors who took her studies seriously.

When Ada was 17, she met an inventor named Charles Babbage. Babbage was building a giant mechanical calculator called the Difference Engine. Later he designed an even bigger machine called the Analytical Engine. The Analytical Engine was meant to do many kinds of math, not just one. It used punched cards, gears, and levers. Babbage never finished building it, but his plans were detailed.

In 1843, Ada translated an article about the Analytical Engine from French into English. She added her own notes to it. Her notes ended up three times longer than the original article. In one of them, called Note G, she wrote out step-by-step instructions for the machine to calculate a tricky list of numbers. That set of instructions is what people now call the first computer program.

Ada saw something in the machine that even Babbage missed. He thought of it as a number cruncher. Ada believed it could do much more. She wrote that one day a machine like this might compose music or make pictures, as long as the rules could be turned into numbers. That idea sounds simple now, but it was a huge leap. Today every song on a phone and every video game runs on the same idea.

Ada called her way of thinking "poetical science." She mixed imagination with math. She died of cancer in 1852, when she was only 36 years old. Her notes were mostly forgotten for nearly 100 years. Then, in the 1950s, scientists building real computers rediscovered them.

Today a programming language called Ada is named after her. The U.S. Department of Defense gave it that name in 1980. Every year in October, schools around the world celebrate Ada Lovelace Day to honor women in science, math, and engineering.