Braille
Channel: 宇宙のすべての知識 プリンシピア
Date: 2019-01-19

Braille, by Wikipedia https://en.wikipedia.org/wiki?curid=3933 / CC BY SA 3.0

#Scripts with ISO 15924 four-letter codes
#Braille
#1824 introductions
#Assistive technology
#Augmentative and alternative communication
#Character sets
#Digital typography
#French inventions
#Latin-script representations
#Scripts encoded in Unicode 3.0
Braille

Braille (; ) is a tactile writing system used by people who are visually impaired. It is traditionally written with embossed paper. Braille users can read computer screens and other electronic supports using refreshable braille displays. They can write braille with the original slate and stylus or type it on a braille writer, such as a portable braille notetaker or computer that prints with a braille embosser.

Braille is named after its creator, Louis Braille, a Frenchman who lost his sight as a result of a childhood accident. In 1824, at the age of fifteen, he developed a code for the French alphabet as an improvement on night writing. He published his system, which subsequently included musical notation, in 1829. The second revision, published in 1837, was the first small binary form of writing developed in the modern era.

These characters have rectangular blocks called "cells" that have tiny bumps called "raised dots". The number and arrangement of these dots distinguish one character from another. Since the various braille alphabets originated as transcription codes for printed writing, the mappings (sets of character designations) vary from language to language, and even within one; in English Braille there are three levels of encoding: Grade 1 – a letter-by-letter transcription used for basic literacy; Grade 2 – an addition of abbreviations and contractions; and Grade 3 – various non-standardized personal stenography.

Braille cells are not the only thing to appear in braille text. There may be embossed illustrations and graphs, with the lines either solid or made of series of dots, arrows, bullets that are larger than bra...