Editing ASCII (section)

{{Short description|A legacy, English-focused character encoding standard}}
{{hatnote group|
{{other uses}}
{{Distinguish|text=MS [[Windows-1252]] or other types of [[extended ASCII]]}}
}}
{{Use mdy dates|date=June 2013|cs1-dates=y}}
{{Use American English|date=December 2018}}
{{Infobox character encoding|
| name = ASCII
| alias = ISO-IR-006,<ref>{{cite iso-ir |number=6 |title=ASCII Graphic character set |id-in-title=yes |sponsor=ANSI |sponsor-link=American National Standards Institute |date=1975-12-01}}</ref> ANSI_X3.4-1968, ANSI_X3.4-1986, ISO_646.irv:1991, ISO646-US, us, IBM367, cp367<ref name="IANA_2007"/>
| mime = us-ascii
| image = USASCII code chart.svg
| caption = ASCII chart from [[MIL-STD-188#MIL-STD-188-100 series|MIL-STD-188-100]] (1972)
| lang = primarily [[English language|English]]; also supports [[Malay language|Malay]], [[Rotokas alphabet|Rotokas]], [[Interlingua]], [[Ido]], and [[X-SAMPA]] <!-- not Latin, see [[Apex (diacritic)]] and [[Interpunct]] -->
| extensions = * [[Unicode]]
* [[ISO/IEC 8859]] (series)
* [[KOI-8]]
* [[OEM code page|OEM]] (series)
* [[Windows-125x]] (series)
* [[Extended ASCII|Others]]
| prev = [[International Telegraph Alphabet No. 2|ITA 2]], [[FIELDATA]]
| next = [[ISO/IEC 8859]], [[ISO/IEC 10646]] ([[Unicode]])
| classification = [[ISO/IEC 646|ISO/IEC 646 series]]
}}
'''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 representing a particular set of 95 ([[English language]] focused) [[printable character|printable]] and 33 [[control character|control]] characters {{endash}} a total of 128 [[code point]]s. The set of available punctuation had significant impact on the syntax of computer languages and text markup. ASCII hugely influenced the design of character sets used by modern computers; for example, the first 128 code points of [[Unicode]] are the same as ASCII.

ASCII encodes each code-point as a value from 0 to 127 {{endash}} storable as a seven-[[bit]] [[integer]].<ref name="RFC-4949">{{cite IETF |title=Internet Security Glossary, Version 2 |date=August 2007 |author-first=R. |author-last=Shirley |rfc=4949 |access-date=2016-06-13}}</ref> Ninety-five code-points are printable, including digits ''0'' to ''9'', lowercase letters ''a'' to ''z'', uppercase letters ''A'' to ''Z'', and commonly used [[punctuation symbol]]s. For example, the letter {{code|i}} is represented as 105 ([[decimal]]). Also, ASCII specifies 33 non-printing [[control code]]s which originated with {{notatypo|[[Teletype Corporation#Teletype Corporation|Teletype devices]]}}; most of which are now obsolete.<ref name="Maini_2007">{{cite book |author-last=Maini |author-first=Anil Kumar |title=Digital Electronics: Principles, Devices and Applications |url=https://books.google.com/books?id=NQSpNAEACAAJ&pg=PA28 |date=2007 |publisher=[[John Wiley and Sons]] |isbn=978-0-470-03214-5 |page=28 |quote=In addition, it defines codes for 33 nonprinting, mostly obsolete control characters that affect how the text is processed.}}</ref> The control characters that are still commonly used include [[carriage return]], [[line feed]], and [[Tab key#Tab characters|tab]].

ASCII lacks code-points for characters with [[diacritical mark]]s and therefore does not directly support [[English terms with diacritical marks|terms or names]] such as [[résumé]], [[jalapeño]], or [[Beyoncé]]. But, depending on hardware and software support, some diacritical marks can be [[Rendering (computer graphics)|rendered]] by overwriting a letter with a [[backtick]] (`) or [[tilde]] (~).

Despite being an American standard, ASCII does not have a code point for the [[Cent (currency)|cent]] (¢). 

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>

ASCII is one of the [[List of IEEE Milestones|IEEE milestones]].<ref>{{Cite web |date=2016-03-29 |title=Milestone-Proposal:ASCII MIlestone - IEEE NJ Coast Section |url=https://ieeemilestones.ethw.org/Milestone-Proposal:ASCII_MIlestone_-_IEEE_NJ_Coast_Section |access-date=2024-02-26 |website=IEEE Milestones Wiki |language=en}}</ref>