Louis Braille — who was born in Coupvray, France, in 1809 — lost his sight when he was just 3 years old. While attending the National Institute for Blind Youth in Paris, he and his classmates yearned for books that were easier to read than those available in the current format. Experimenting with different ways to read through touch, he expanded upon the tactile "Ecriture Nocturne,” a night-reading military code that was designed for reading messages on the battlefield in the dark. In 1824, at the age of 15, he invented Braille; in 1829, he published it. The second revision, published in 1837, is considered the first digital (binary) form of writing.