Braille

Braille is a tactile writing system used by blind or visually impaired people, read either from paper embossed with raised dots or from refreshable electronic braille displays connected to computers or smartphones, and it can also be written with a slate and stylus, a braille writer, an electronic notetaker, or a computer linked to a braille embosser. It was created in 1824 by fifteen year old Frenchman Louis Braille, who had lost his sight in a childhood accident, as an improvement on an earlier system called night writing, and he published his code, later extended to musical notation, in 1829, with a revised binary form following in 1837. Each braille character is built from a cell of six raised dots arranged in a three by two grid, giving 64 possible combinations that can represent letters, digits, punctuation, whole words, or a blank space. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/