On Apr 23, 2007, at 10:52 AM, Arnaud Nicolet wrote: > Le 23 avr. 07 à 18:43 Soir, [EMAIL PROTECTED] a écrit: > >> No, legacy encodings were defined all over the world. Unicode was >> defined by an international consortium. > > Thank you. > I wonder, then, why those encodings also include the ASCII part. > Should not the ASCII be an independent encoding?
There is a good overview of the evolution of ASCII and ASCII-based encodings at Wikipedia under "ASCII". As I remember (and I am getting old, so take it with a grain of salt): In the beginning, everyone who decided to build a machine (computer or terminal) created their own encodings. And countries with other languages created their own encodings as fitted there needs. Being old and from the U.S., the only other codes that immediately come to mind are EBCDIC and ANSEL. But there were others. As computers began to talk to each other, it became clear that if IBM used one encoding and DEC used another and Univac still another, things could get complicated. A standards committee was called, and ASCII was born (in the U.S.). Like it or not, with big businesses pushing and government incentives, the U.S. became the center of the computing world. Computing spread from the U.S. outward. Since U.S. encodings had a standard, it was easy to use it as a base for other encodings in other countries, adding need characters in the unused (and non- existent) "high-ASCII" range. The birth of microcomputers (as they were called back in the day), created more problems with ASCII. Most agreed on ASCII as a base, but used the un-defined higher characters for whatever seemed appropriate to their intended audience. "High-ASCII" got filled with space ships, smiley faces, greek letters, graphic borders, etc. Word Perfect got very creative allowing you to switch between sets of extended ASCII encodings depending on your need. But just as U.S. communications necessitated the creation of ASCII, world-wide communications and file sharing between platforms soon demanded standards. Some advocated dumping all existing standards and creating a new universal standard -- a 16- or 32-bit encoding capable of representing all characters from all languages with room to grow. In the end, it was decided to build on existing standards rather than replace them. And a scaleable encoding scheme was created allowing us to keep our good old 7-bit ASCII as a base and build on it. Unicode was born. Sadly Windows, Macintosh, and Postscript character sets were all created (independently) before the international standard. So they can still give us problems. Sometimes I wonder if they might have been right to dump everything and start fresh. The transition would have been rocky, but encoding problems would by now be a thing of the past. Kirk ----------------------------------------------- REALbasic Professional 2007r1 MacBook Core Duo, Mac OS X 10.4.9 _______________________________________________ Unsubscribe or switch delivery mode: <http://www.realsoftware.com/support/listmanager/> Search the archives: <http://support.realsoftware.com/listarchives/lists.html>
