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Braille system


Braille  is a tactile writing system used by the blind and the visually impaired. It is traditionally written with embossed paper. Braille-users can read computer screens and other electronic supports thanks to 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 note-taker, or on a computer that prints with a braille embosser. Braille is named after its creator, Frenchman Louis Braille, who went blind following a childhood accident. In 1824, at the age of 15, Braille developed his code for the French alphabet as an improvement on night writing. He published his system, which subsequently included musical notation, in 1829.[2] The second revision, published in 1837, was the first digital (binary) form of writing.

Braille characters are small rectangular blocks called cells that contain tiny palpable 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 of printed writing systems, the mappings (sets of character designations) vary from language to language. Furthermore, 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 shorthands. Braille cells are not the only thing to appear in embossed 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 braille dots, etc. In the face of screen-reader software, braille usage has declined. However, braille education remains important for developing reading skills among blind and visually impaired children, and braille literacy correlates with higher employment rates.

Braille was based on a tactile military code called night writing, developed by Charles Barbier in response to Napoleon's demand for a means for soldiers to communicate silently at night and without light. In Barbier's system, sets of 12 embossed dots encoded 36 different sounds. It proved to be too difficult for soldiers to recognize by touch, and was rejected by the military. In 1821 Barbier visited the Royal Institute for the Blind in Paris, where he met Louis Braille. Braille identified two major defects of the code: first, by representing only sounds, the code was unable to render the orthography of the words; second, the human finger could not encompass the whole 12-dot symbol without moving, and so could not move rapidly from one symbol to another. Braille's solution was to use 6-dot cells and to assign a specific pattern to each letter of the alphabet.[3] At first, braille was a one-to-one transliteration of French orthography, but soon various abbreviations, contractions, and even logograms were developed, creating a system much more like shorthand.[4] The expanded English system, called Grade-2 Braille, was complete by 1905. For the blind today, braille is an independent writing system rather than a code of printed orthography.[5]

Derivation

Braille is derived from the Latin alphabet, albeit indirectly. In Braille's original system, the dot patterns were assigned to letters according to their position within the alphabetic order of the French alphabet, with accented letters and w sorted at the end.[6]The first ten letters of the alphabet, a–j, use the upper four dot positions: (black dots in the table below). These stand for the ten digits 1–9 and 0 in a system parallel to Hebrew gematria and Greek isopsephy. (Though the dots are assigned in no obvious order, the cells with the fewest dots are assigned to the first three letters (and lowest digits), abc = 123 (), and to the three vowels in this part of the alphabet, aei (), whereas the even digits, 4, 6, 8, 0 (), are corners / right angles.)The next ten letters, k–t, are identical to a–j, respectively, apart from the addition of a dot at position 3 (red dots in the table): :

Unicode rendering table 

The Unicode standard encodes 8-dot braille glyphs according to their binary appearance, rather than following their assigned numeric order. Unicode defines the character block "Braille Patterns" in the hex code-point range of 2800 to 28FF. Dot 1 corresponds to the least significant bit of the low byte of the Unicode scalar value, and dot 8 to the high bit of that byte. Most braille embossers and refreshable braille displays do not support Unicode, using instead 6-dot braille ASCII. Because of this, they are unable to display this article. Some embossers have proprietary control codes for 8-dot braille or for full graphics mode, where dots may be placed anywhere on the page without leaving any space between braille cells, so that continuous lines can be drawn in diagrams, but these are rarely used and are not standard.

Page dimensions

Most braille embossers support between 34 and 37 cells per line, and between 25 and 28 lines per page. A manually operated Perkins braille typewriter supports a maximum of 42 cells per line (its margins are adjustable), and typical paper allows 25 lines per page. A large interlining Stainsby has 36 cells per line and 18 lines per page. An A4-sized Marburg braille frame, which allows interpoint braille (dots on both sides of the page, offset so they do not interfere with each other) has 30 cells per line and 27 lines per page.

Literacy 

A sighted child who is reading at a basic level should be able to understand common words and answer simple questions about the information presented.[9] The child should also have enough fluency to get through the material in a timely manner. Over the course of a child's education, these foundations are built upon in order to teach higher levels of math, science, and comprehension skills.[9] Children who are blind not only have the educational disadvantage of not being able to see, but they also miss out on the very fundamental parts of early and advanced education if not provided with the necessary tools.

U.S. braille literacy statistics

In 1960, 50% of legally blind, school-age children were able to read braille in the U.S.[10][11] According to the 2011 Annual Report from the American Printing House for the Blind, there are approximately 58,939 legally blind children in the U.S aged 0–21. Of these, about 9% prefer braille as their primary reading medium; 27% are visual readers, 8% are auditory readers, 21% are pre-readers, and 34% are non-readers.[12]There are numerous causes for the decline in braille usage, including school budget constraints, technology advancement, and different philosophical views over how blind children should be educated.[13]
A key turning point for braille literacy was the passage of the Rehabilitation Act of 1973, an act of Congress that moved thousands of children from specialized schools for the blind into mainstream public schools.[11] Because only a small percentage of public schools could afford to train and hire braille-qualified teachers, braille literacy has declined since the law took effect.[clarification needed][11] Braille literacy rates have improved slightly since the bill was passed,[clarification needed] in part because of pressure from consumers and advocacy groups that has led 27 states to pass legislation mandating that children who are legally blind be given the opportunity to learn braille.[13]

In 1998–99, there were approximately 55,200 legally blind children in the United States, but only 5,500 of them used braille as their primary reading medium.[14][15] Early Braille education is crucial to literacy for a visually impaired child. A study conducted in the state of Washington found that people who learned braille at an early age did just as well, if not better, than their sighted peers in several areas, including vocabulary and comprehension. In the preliminary adult study, while evaluating the correlation between adult literacy skills and employment, it was found that 44% of the participants who had learned to read in braille were unemployed, compared to the 77% unemployment rate of those who had learned to read using print.[16] Currently, among the estimated 85,000 blind adults in the United States, 90% of those who are braille-literate are employed. Among adults who do not know braille, only 33% are employed.[11] Statistically, history has proven that braille reading proficiency provides an essential skill set that allows visually impaired children not only to compete with their sighted peers in a school environment, but also later in life as they enter the workforce.[13]

United Kingdom

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.[17] Younger people are turning to electronic text on computers with screen reader software 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.
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