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→8-bit codes: the term "extended ASCII" has no official status. |
Unicode does not have millions of code points anymore. It is limited to 17 planes of 65536 characters each, about 1.1 million. |
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| classification = [[ISO/IEC 646|ISO/IEC 646 series]]
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'''ASCII''' ({{IPAc-en|audio=En-us-ASCII.ogg|ˈ|æ|s|k|iː}} {{respell|ASS|kee}}),<ref name="Mackenzie_1980">{{cite book |url=https://textfiles.meulie.net/bitsaved/Books/Mackenzie_CodedCharSets.pdf |title=Coded Character Sets, History and Development |series=The Systems Programming Series |author-last=Mackenzie |author-first=Charles E. |date=1980 |edition=1 |publisher=[[Addison-Wesley Publishing Company, Inc.]] |isbn=978-0-201-14460-4 |lccn=77-90165 |pages=6, 66, 211, 215, 217, 220, 223, 228, 236–238, 243–245, 247–253, 423, 425–428, 435–439 |access-date=2019-08-25 |archive-url=https://web.archive.org/web/20160526172151/https://textfiles.meulie.net/bitsaved/Books/Mackenzie_CodedCharSets.pdf |archive-date=May 26, 2016 |url-status=live |df=mdy-all }}</ref>{{rp|6}} an acronym for '''American Standard Code for Information Interchange''', is a [[character encoding]] standard for electronic communication. ASCII codes represent text in computers, [[telecommunications equipment]], and other devices. Because of technical limitations of computer systems at the time it was invented, ASCII has just 128 [[code point]]s, of which only 95 are {{Pslink|printable characters}}, which severely limited its scope. Modern computer systems have evolved to use [[Unicode]], which has
The [[Internet Assigned Numbers Authority]] (IANA) prefers the name '''US-ASCII''' for this character encoding.<ref name="IANA_2007">{{cite web|website=Internet Assigned Numbers Authority (IANA)|date=May 14, 2007|url=https://www.iana.org/assignments/character-sets|title=Character Sets|access-date=2019-08-25}}</ref>
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IBM defined [[code page 437]] for the [[IBM PC]], replacing the control characters with graphic symbols such as [[Emoticon|smiley faces]], and mapping additional graphic characters to the upper 128 positions.<ref>{{cite book |url=http://www.bitsavers.org/pdf/ibm/pc/pc/6025008_PC_Technical_Reference_Aug81.pdf |title=Technical Reference |at=Appendix C. Of Characters Keystrokes and Color |edition=First |date=August 1981 |series=Personal Computer Hardware Reference Library |publisher=IBM}}</ref> [[Digital Equipment Corporation]] developed the [[Multinational Character Set]] (DEC-MCS) for use in the popular [[VT220]] [[computer terminal|terminal]] as one of the first extensions designed more for international languages than for block graphics. [[Apple Inc.|Apple]] defined [[Mac OS Roman]] for the Macintosh and [[Adobe Inc.|Adobe]] defined the [[PostScript Standard Encoding]] for [[PostScript]]; both sets contained "international" letters, typographic symbols and punctuation marks instead of graphics, more like modern character sets.
The [[ISO/IEC 8859]] standard (derived from the DEC-MCS) provided a standard that most systems copied (or at least were based on, when not copied exactly). A popular further extension designed by Microsoft, [[Windows-1252]] (often mislabeled as [[ISO-8859-1]]), added the typographic punctuation marks needed for traditional text printing. ISO-8859-1, Windows-1252, and the original 7-bit ASCII were the most common character
[[ISO/IEC 4873]] introduced 32 additional control codes defined in the 80–9F [[hexadecimal]] range, as part of extending the 7-bit ASCII encoding to become an 8-bit system.<ref name="Unicode-5.0_2006">{{cite book |author=The Unicode Consortium |editor-first=Julie D. |editor-last=Allen |title=The Unicode standard, Version 5.0 |date=2006-10-27 |publisher=[[Addison-Wesley Professional]] |location=Upper Saddle River, New Jersey, US |isbn=978-0-321-48091-0 |chapter-url=http://unicode.org/book/ch13.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://unicode.org/book/ch13.pdf |archive-date=2022-10-09 |url-status=live |access-date=2015-03-13 |chapter=Chapter 13: Special Areas and Format Characters |page=314}}</ref>
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