This week is National Braille Week in honour of Louis Braille, who was born 200 years ago. Louis Braille was totally blind by the age of four after an accident in his father's saddlery workshop. He was sent away to a special school for blind children, who, at the time, were mostly trained in practical skills, such as chair-caning. At the time books for blind people used a system where individual letters were raised from the page, and reading was a very slow and laborious activity.
Louis was only in his early teens when he got the idea for a coded system of raised dots to represent the letters of the alphabet. The idea was suggested to him after a visit to the school by Captain Charles Barbier of Napoleon's army, who demonstrated a system known as Ecriture Nocturne (night writing) used by soldiers to send and receive messages on the battlefield at night. Louis simplified Barbier's system so that just six dots were used. There was much resistance over the following decades to the Braille reading system (no doubt because the influential people of the day were sighted) and it wasn't until 1952 that the French government finally recognised Louis Braille's accomplishments and exhumed his body, reburying him alongside other French national heroes in the Pantheon. Today Braille is used throughout the world, regardless of language.
There are 63 possible combinations of the six dots and these represent all the letters of the alphabet, punctuation marks and commonly occurring clusters of letters. Computers are increasingly becoming able to deal with Braille, eg you can type in ordinary text and it prints off as Braille, or you can have Braille symbols on the keyboard. Braille is not a language in itself, but is a code into which any language can be 'translated'. The website of the RNIB (Royal National Institute for Blind People) gives lots more of information about Braille.
It's not only blind people who find Braille invaluable. A friend of mine, who teaches at a school for blind children, showed me some of the texts that she and her colleagues had exchanged. I found it hard to understand them because they used different abbreviations from those most people use when texting. For instance, I would type b to mean 'be' and c to stand for 'see', whereas my friend meant 'but' by b and 'can' by c, which are standard Braille abbreviations.