Braille

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This Braille spells "premier" which is French for first

The Braille system is a way of writing things. It is named after Louis Braille, the French man who invented it. The system is used by blind people to read and write. The Braille system uses a set of raised bumps or dots that can be felt with a finger. Each set of dots is a character in an alphabet, and the numbers and some punctuation.

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[change] Before Braille

Louis Braille was not the first person to think about how to let the blind read and write. In the 17th century the Italian Jesuit Francesco Lana thought about different systems of writing for the blind. He invented a system of dashes that could be felt.[1]

Valentin Haüy was one of the first French who was interested in the problems the blind had when they wanted to communicate. Haüy was born in Picardie in 1745, and studied languages at the university in Paris. First he studied deaf people who could not speak, then blind people. In his opinion the biggest problem of the blind was that they could not read. He then invented a system which allowed them to read and write sentences and mathematics. Later he started a school for blind children. His writing system used two columns which had between one and six positions each. Vowels had a dot in the left column, for example.

The Braille system was based on a method of communication originally developed by Charles Barbier. Barbier made it because Napoleon wanted a code that soldiers could use to exchange messages silently and without light at night. Barbier called it night writing. Night writing uses two columns of six dots. It uses phonemes, not letters. Barbier's system was too complex for soldiers to learn, the military rejected it. From the year 1821, he started to test his system in the school Haüy had founded. There it became very successful. Even though the system was difficult to learn, it greatly improved on reading. Barbier had understood that it was better to use a system that used dots over one that used lines.

When Barbier met Braille when he visited the National Institute of the Blind. Braille saw the biggest problem of the code: The human finger cannot feel the whole symbol without moving. This makes it impossible to move rapidly from one symbol to the next. Braille's change was to use a 6 dot cell — the braille system — which revolutionized written communication for the blind.

[change] The Braille alphabet

Braille can be seen as the world's first binary character encoding. The system as originally invented by Braille has two parts

  1. A way of representing the characters of the French language with tuples of six bits or "dots".
  2. A way of representing six-bit characters as raised dots in Braille cell.

Braille is used with different languages today. In each language, the letters are encoded differently, the same letter is at a different position in the alphabet. This is known as braille code, or code page. There are also different braille codes in use for special purposes, like writing shorthand, mathematics or music.

To make it possible to read faster, certain transcriptions of Braille use contractions. This is known as Grade 2 Braille.

[change] The Braille cell

Braille cell
Braille alphabet (letters only)

Braille uses cells of six raised dots, in two columns of three dots. The dot positions on the left are numbered one, to three, the ones on the right four to six, as shown in the picture.

Each symbol is coded with certain dots present, and others absent. The dots are approximately 0.02 inches (0.5 mm) high; inside the cell, the dots are about 0.1 inches (2.5 mm) apart. The space between the dots of two cells is about 0.15 inches (3.75 mm) horizontally and 0.2 inches (5 mm) vertically. A standard braille page is 11 inches by 11 inches and typically has between forty and forty-two braille cells per line and twenty-five lines.

[change] Encoding

As originally conceived by Louis Braille, a sequence of characters, using the top 4 dots of the braille cell, represents letters "a" through "j". Dot 3 is added to each of the "a" through "j" symbols to give letters "k" through "t". Both of the bottom dots (dots 3 and 6) are added to the symbols for "a" through "e" to give letters "u", "v", "x", "y", and "z". The letter "w" is an exception to the pattern because French did not make use of the letter "w" at the time Louis Braille devised his alphabet, and thus he had no need to encode the letter "w".

English braille codes the letters and punctuation, and some double letter signs and word signs directly, but capitalization and numbers are dealt with by using a prefix symbol. In practice, braille produced in the United Kingdom does not have capital letters.

There are braille codes for representing shorthand (produced on a machine which embosses a paper tape) and for representing mathematics (Nemeth Braille) and musical notation (braille music).

[change] Writing braille

Braille can be made using a "slate" and a "stylus" in which each dot is created from the back of the page, writing in mirror image, by hand, or it may be produced on a braille typewriter or "Perkins Brailler", or produced by a braille embosser attached to a computer. It may also be rendered using a refreshable braille display.

[change] Extensions

The six code braille is very limited, it only allows 64 different combinations. Keeping to the 6-bit code means that many things need more than one braille character to be coded. A good example for this is how numbers are coded: First there is a symbol that says the next symbol is a number, and then there is the symbol for the number. Louis Braille coded the number 1 the same way as a, 2 the same as b, and so on. The letter i can also mean 9, and j stands for the zero. There is another system for coding numbers, called Antoine. This comes from mathematics. It uses one character to say there is a number (dot 6), and then there are 10 different symbols for the 10 digits. The symbol for number is usually given only once; every symbol that follows is treated as a number, until there is a space.

Braille has been extended to an 8 dot code, particularly for use with braille embossers and refreshable braille displays. In 8 dot braille the additional dots are added at the bottom of the cell, giving a matrix 4 dots high by 2 dots wide. The additional dots are given the numbers 7 (for the lower-left dot) and 8 (for the lower-right dot). 8-dot braille has the advantages that the case of an individual letter is directly coded in the cell containing the letter and that all the printable ASCII characters can be represented in a single cell. All 256 possible combinations of 8 dots are encoded by the Unicode standard. Braille with six dots is frequently stored as braille ASCII.

[change] Braille transcription

[change] Grade 1 braille

Braille Writer
Braille on a packet of drugs.
Braille book and the same book in common letters

It is possible to transcribe braille by replacing each letter with its braille counterpart. This is usually known as Grade 1 Braille. Grade 1 braille is mostly used by beginners.

The basic problem of Grade 1 braille is that braille letters are much larger than printed ones. The standard page is 11"x11" (28 cm by 28 cm) in size and only has room for twenty-five lines of forty characters.

[change] Grade 2 braille

For this reason almost all braille books use a transcription known as Grade 2 braille. Grade 2 braille uses contractions, which allows to save space and increase reading speed. Grade 2 braille was developed by linguists who also looked at customs, styles and practices. Transcribing a text into Grade 2 braille is difficult, and the people doing the transcription need to have a special education. There is a book on how to transcribe to braille, in the Library of Congress. This book has almost 200 pages.

In English, there are 23 words which are replaced with a single letter. That way, the word but is contracted to the single letter b, can to c, do to d, and so on. Even this simple rule has exceptions and special cases, which must be thought of. As an example, only the verb to do is replaced by d, the noun do (which stands for a note in music) is a different word, and is written in full.

Sometimes, portions of words are contracted. There are many rules for this process. For example, the character with dots 2-3-5 (the letter "f" lowered in the braille cell) stands for "ff" when used in the middle of a word. At the beginning of a word, this same character stands for the word "to" although the character is written in braille with no space following it. At the end of a word, the same character represents an exclamation point.

The contraction rules take into account the linguistic structure of the word; thus, contractions are not to be used when their use would alter the usual braille form of a base word to which a prefix or suffix has been added. In addition, some portions of the transcription rules are not fully codified and rely on the judgment of the transcriber. Thus, when the contraction rules permit the same word in more than one way, preference is given to "the contraction that more nearly approximates correct pronunciation."

[change] Grade 3 braille

Grade 3 Braille is a system that includes many additional contractions. It is almost like a shorthand. It is rarely used for publications, rather people use it to be able to write and read fast, for themselves.

[change] Grade 4 braille

Only very few people can use grade 4 braille. It uses many rules to shorten grade 3 even further. It allows a blind person to use shorthand to follow spoken conversation. Very often, systems of seven or eight dots are used.

[change] Braille on banknotes

The current series of Canadian banknotes have raised dots on the banknotes that indicate their value. They can be easily identified by visually impaired people; this 'tactile feature' does not use standard braille but, instead, a system developed in consultation with blind and visually impaired Canadians after research indicated that not all potential users read braille.

[change] Writing systems other than braille

Though braille is thought to be the main way blind people read and write, in Britain (for example) out of the reported 2 million visually impaired population, it is estimated that only around 15-20 thousand people use Braille. Younger people are turning to electronic text on computers instead; a more portable communication method that they can also use with their friends. A debate has started on how to make braille more attractive and for more teachers to be available to teach it.

[change] Braille for other scripts

There are many extensions of Braille for additional letters with diacritics, such as ç, ô, é.

When braille is adapted to languages which do not use the Latin alphabet, the blocks are generally assigned to the new alphabet according to how it is transliterated into the Latin alphabet, and the alphabetic order of the national script (and therefore the natural order of Latin braille) is disregarded. Such is the case with Russian, Greek, Hebrew, Arabic, and Chinese. In Greek, for example, gamma is written as Latin g, despite the fact that it has the alphabetic position of c; Hebrew beth, the second letter of the alphabet and cognate with the Latin letter b, is instead written v, as it is commonly pronounced; Russian ts is written as c, which is the usual letter for /ts/ in those Slavic languages that use the Latin alphabet; and Arabic f is written as f, despite being historically p, and occurring in that part of the Arabic alphabet (between historic o and q). Esperanto letters with circumflexes, ĉ, ĝ, ĥ, ĵ and ŝ, are written as those letters without circumflexes with a filled sixth dot. The ŭ, used in Esperanto too, is as the u but the first dot is moved to the second place.

Greater differences occur in Chinese braille. In the case of Mandarin Braille, which is based on Zhuyin rather than the Latin Pinyin alphabet, the traditional Latin braille values are used for initial consonants and the simple vowels. However, there are additional blocks for the tones, diphthongs, and vowel + consonant combinations. Cantonese Braille is also based on Latin braille for many of the initial consonants and simple vowels (based on Romanizations of a century ago), but the blocks pull double duty, with different values depending on whether they are placed in syllable-initial or syllable-final position. For instance, the block for Latin k represents old-style Cantonese k (g in Yale and other modern Romanizations) when initial, but aak when final, while Latin j represents Cantonese initial j but final oei.

However, at least two adaptations of Braille have completely reassigned the Latin sound values of the blocks. These are:

In Japanese Braille, alphabetic signs for a consonant and vowel are combined into a single syllabic block; in Korean Braille, the consonants have different syllable-initial and syllable-final forms. These modifications made Braille much more compatible with Japanese kana and Korean hangul, but meant that the Latin sound values could not be maintained.

[change] Reading Braille

Trained readers of Braille can read about 100 words per minute; trained readers who do not have sight problems can get to around 250 to 300 words per minute.

[change] Other pages

[change] Other websites

[change] References