Leonardo da Vinci is most famous for paintings like the Mona Lisa and The Last Supper. But painting was only part of what he did. He was also an inventor, an engineer, a musician, and one of the first people to dissect human bodies to draw exactly how muscles and bones fit together.
He carried small notebooks everywhere and filled them with anything that caught his eye: birds in flight, water swirling around rocks, ideas for parachutes, scuba gear, and machines that looked a lot like modern helicopters and tanks. He never built most of them - but the designs would have worked.
To keep his ideas private (and maybe because he was left-handed and it was easier), he wrote in mirror writing - letters and words flipped backwards. About 7,000 pages of his notebooks survive, and scientists are still finding ideas in them that nobody had noticed before.
