Louis Braille lost his sight in an accident when he was three years old. At his school for blind children in Paris, books were huge and almost useless. Each letter was pressed into thick paper, and reading one page took many minutes.
One day, a soldier visited the school and showed a secret military code of raised dots. Soldiers used it to read messages in the dark without light. Young Louis saw something the adults had missed: dots could be a whole alphabet.
He spent three years improving the system and finished it at age fifteen. His alphabet used just six dots to write every letter, number, and even music. Today, blind people in every country read with the system a teenager created two hundred years ago. Sometimes the freshest ideas come from the youngest minds.