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The following appears on web pages of the AFB Solutions Forum and is used with permission.
Author - Electronic Files and Research and Development Work Group: Janina Sajka and Jim Allan
American Standard Code for Information Interchange (ASCII) is the basis of character sets used in almost all present day computers. The roots of ASCII reach back to the typewriter, and particularly to the teletypewriter. Today's computers offer characters from most foreign languages-and offer them in sizes and font faces never available in the typewriter age. Also, the ASCII character set never provided information that could help a user navigate information. Strategies such as bold and italics were never available in the typewriter age-to say nothing of the kind of navigation riches that web technologies provide.
Still, ever since computers became affordable, a plain ASCII text file has provided print-disabled readers access to published information. Getting a book or a document as a plain ASCII text file has become almost synonymous with getting an accessible copy. This is because ASCII files have provided information (content) that could be used with any computer. However, an ASCII textfile only provides the text or content of the document (though primarily in English), all spaces, most of the punctuation, and all the line breaks in the document. All positional formatting (paragraph indents, centering, headings, etc.) is accomplished by inserting blank spaces and carriage returns-just as it would be on a typewriter. With ASCII, the structure and details of the page are not embedded in the coded text. Because ASCII provides only content and no information about document structure or presentation, it is no longer a good choice for mass production of accessible textbooks and curricular materials. The time has come to transition from ASCII text files toward new electronic file formats.
Newly available electronic file formats can provide everything an ASCII text file ever provided the print-disabled reader-and far more. For example, file formats that facilitate producing properly formatted braille on a variety of paper sizes or devices, also provide the needed information for the construction of books with synchronized audio and electronic text.
The plain truth is that ASCII is very old. It may surprise you to learn that ASCII has been in use long before computers. In fact its roots go back to the 19th Century. Just as automobiles replaced the horse and buggy and computers replaced typewriters, new technologies are at hand to provide a superior level of access that is international in scope.
A plain ASCII textfile has no markup commands or codes that indicate formatting (structure or presentation) information (headings and fonts). It cannot indicate bold and italic text. It cannot provide codes that indicate the structure of the document such as chapter and section headings. ASCII cannot provide proportional fonts, or characters for foreign languages. All this information (markup) must be added into a plain ASCII text file by hand in order to produce good braille books. It will never provide the markup coding available in Hypertext Markup Language (HTML) and especially Extensible Markup Language (XML), which are the languages of the web.
In addition, the "structure" that plain-ASCII leaves out (or handles inadequately) is not only important to document structure but also to the very meaning of mathematical expressions involving powers, fractions, radicals, etc. With the right coding, these can be quickly and accurately put into braille (as well as in print and speech). Therefore, a typical plain-ASCII presentation of math is almost useless for automated transcription purposes.
ASCII files are also comparatively difficult to read using speech synthesis. We must look forward to new tools such as the Digital Talking Book (DTB), debuting in 2000. The DTB supports all structural and character markup available from HTML/XML. As we transition to these new formats, existing files of classic literature, archived documents, and other ASCII files created with older computer tools must remain accessible to individuals with disabilities and those using older software and hardware. But this does not mean that we cannot make progress and the DTB is a major improvement on ASCII, particularly because it facilitates navigation through a book so well.
We should not start any new programs based on ASCII. ASCII will continue to be appropriate for simple email messages-and "quick and dirty" text access, and archived literature and documents, but it is no longer a responsible choice for today's educator. It has too many limitations for timely and accurate braille production. A base requirement for files used in the production of braille textbooks should be a file that is based on a recognized markup with full capabilities for character and structural formatting. Files created using a markup language can be easily reformatted for different paper sizes or for presentation on a refreshable braille display. An already marked up file can be made into a braille book in a more timely fashion because all structure and formatting for braille production does not need to be added into the file. A fully-structured and marked-up electronic file will assist in a smooth transition from the publishers' electronic files to the production of textbooks in braille.
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