Louis Braille, who was blinded as a child, invented the Braille system at the age of 15. He adapted a military code called 'night writing' (used by soldiers to read messages in the dark without light) into a more efficient six-dot cell system. Each cell represents a letter, number, or musical note, allowing blind people to read and write through touch. Before this, blind people had to read using bulky, embossed letters that were difficult to produce and slow to read. Braille's invention revolutionized education and literacy for the visually impaired, granting them independence and access to literature, science, and music. It has since been adapted into nearly every language in the world.