Braille, the universal system for reading and writing used by people who are blind or visually impaired was invented by a teenager.

LOUIS BRAILLE (1809–1852) was born in Coupvray, a town in north central France, on January 4, 1809. At the age of three, he accidentally blinded himself in one eye with a stitching awl taken from his father's leather workshop. His other eye went blind because of sympathetic ophthalmia, an inflammation of both eyes following trauma to one.

After hearing a presentation on a system called "night writing" created by Charles Barbier, he became inspired to improve it and began experimenting with a raised dot system that would be an improvement upon the existing embossed letter system that was currently being used to teach reading to the visually impaired.

In 1825, just barely 16-years old, Braille created a code of six dots arranged in two parallel rows, each set of rows representing a letter. This configuration was simpler than Barbier’s system, but still versatile enough to allow for up to 64 variations, enough for all the letters of the French alphabet and punctuation.

By the later nineteenth century braille had been adopted throughout most of the world, except the US, who held out until 1916.