Editing Space (punctuation) (section)

==Use in natural languages==

===Between words===
{{Main article|Word divider}}
{{Expert-subject|Linguistics|reason=At some point, this subsection contained a lot of incorrect claims about Semitic languages, and weasel-wording. It was clearly written by someone who doesn’t know any of the relevant languages. Some claims remain largely unsupported and Euro-centric. This needs attention from a historical linguist. If such an expert can’t be found, it is better to rewrite this with a focus on developments within individual writing systems – which is ''not'' how it’s structured at the moment.|date=August 2023}}

Modern English uses a space to separate words, but not all languages follow this practice. According to Paul Saenger in ''Space Between Words: The Origins of Silent Reading,'' [[Biblical Hebrew|Ancient Hebrew]] and [[Arabic]] did use spaces partly to compensate in clarity for the [[Abjad|lack of written vowels]] when no {{Lang|la|[[mater lectionis]]}} was used for a vowel, though in the Middle Ages they sometimes omitted spaces when vowel points were marked.<ref>[https://books.google.com/books?id=w3vZaFoaa3EC&pg=PA10 Saenger 2000, 10]: “the Semitic languages (Hebrew, Aramaic, Arabic, and Syriac), when written without vowels, were virtually always written with word separation in antiquity and continued to be so transcribed into modern times”</ref> The earliest Greek script also used interpuncts to divide words rather than spacing, although this practice was soon displaced by the {{Lang|la|[[scriptio continua]]}}. In [[Latin]], spaces and interpuncts came often to be dropped in favor of {{Lang|la|scriptio continua}}, and were not used to separate words again until roughly AD 600–800.

Word spacing was later used by Irish and Anglo-Saxon scribes, beginning after the creation of the [[Carolingian minuscule]] by [[Alcuin of York]] and the scribes’ adoption of it. Spacing would become standard in [[Renaissance]] Italy and France, and then [[Byzantium]] by the end of the 16th century; then entering into the Slavic languages in [[Cyrillic]] in the 17th century, and only in modern times entering modern [[Sanskrit]].<ref>Saenger, Paul. ''Space Between Words: The Origins of Silent Reading''. Stanford University Press, 1997, 9–14.</ref>{{dubious|reason=Word spacing was used in Byzantine manuscripts well before the 16th century.|date=March 2024}}

[[CJK characters|CJK]] languages do not use spaces when dealing with text containing mostly [[Chinese characters]] and [[kana]]. In [[Japanese language|Japanese]], spaces may occasionally be used to separate people’s [[family name]]s from [[given name]]s, to denote omitted [[Japanese particles|particles]] (especially the topic particle ''wa''), and for certain literary or artistic effects. Modern [[Korean language|Korean]], however, has spaces as an essential part of its writing system (because of Western influence), given the phonetic nature of the [[hangul]] script that requires word dividers to avoid ambiguity, as opposed to Chinese characters which are mostly very distinguishable from each other. In Korean, spaces are used to separate chunks of nouns, nouns and [[Korean postpositions|particles]], adjectives, and verbs; for certain compounds or phrases, spaces may be used or not, as in the phrase for “[[Republic of Korea]],” usually spelled without spaces as {{lang|ko|대한민국}} rather than with a space as {{lang|ko|대한 민국}}.

[[Runic]] texts use either an [[interpunct]]-like or a [[colon (punctuation)|colon]]-like punctuation mark to separate words. There are two [[Unicode]] characters dedicated for this: {{unichar|16EB|Runic single punctuation}} and {{unichar|16EC|Runic multiple punctuation}}.

===Between sentences===
{{Main article|Sentence spacing}}

Languages with a Latin-derived alphabet have used various methods of sentence spacing since the advent of movable type in the 15th century.

* One space (some times called ''[[French spacing]]'', ''q.v.''). This is a common convention in most countries that use the [[ISO basic Latin alphabet]] for published and final written work, as well as digital (World Wide Web) media.<ref>
{{cite book
 | title= The Copyeditor's Handbook: A Guide for Book Publishing and Corporate Communications
 | edition= 2nd
 | last = Einsohn
 | first= Amy
 | year = 2006
 | publisher= University of California Press
 | location= Berkeley, Los Angeles, London
 | isbn = 9780520246881
 | page = 113
 | chapter= Punctuation, Eyeballing every mark
 | chapter-url= https://books.google.com/books?id=fnhkJ_CjTQIC&pg=PA113 
 | quote = If you are working on documents that will be printed without any intervention from a compositor (e.g., documents produced on the office laser printer), you will have to carefully scrutinize every piece of punctuation to be sure that the document contains the correct character (see table 5). You should also delete any extra wordspacing before and after punctuation marks. The conventions are: One space follows sentence-ending punctuation mark (period, question mark, or exclamation point). One space follows comma, colon, or semicolon ...
 | access-date= 2010-04-25
 }}</ref> [[Web browser]]s usually do not differentiate between single and multiple spaces in source code when displaying text, unless the text is given a "white-space" [[Cascading Style Sheets|CSS]] attribute. Without this being set, [[Whitespace collapsing|collapsing strings of spaces to a single space]] allow HTML source code to be spaced in a more machine-readable way, at the expense of control over the spacing of the rendered page.<ref>{{cite web|url=http://www.tomsarazac.com/tom/opinions/space-after-periods.html |date=February 2012 |orig-date=May 2011 |website=Tom Sara Zac |title=How many spaces at the end of a sentence? One or two?|author=Thomas A. Fine|access-date=2013-08-08|archive-date=2014-02-20|archive-url=https://web.archive.org/web/20140220233010/http://www.tomsarazac.com/tom/opinions/space-after-periods.html|url-status=live}}</ref>
* Double space (''[[English spacing]]''). It is sometimes claimed that this convention stems from the use of the [[monospaced font]] on [[typewriters]].<ref>{{cite magazine|title=Space Invaders: Why you should never, ever use two spaces after a period.|url=http://www.slate.com/id/2281146/|author=Farhad Manjoo|date=2011-01-13|magazine=[[Slate (magazine)|Slate]]|access-date=2011-03-29}}</ref> However, instructions to use more spacing between sentences than words date back centuries, and two spaces on a typewriter was the closest approximation to typesetters' previous rules aimed at improving readability.<ref>{{cite web|url=http://www.heracliteanriver.com/?p=324|title=Why two spaces after a period isn't wrong|author=Heraclitus|date=1 November 2011|access-date=8 August 2013|archive-date=26 July 2013|archive-url=https://web.archive.org/web/20130726225645/http://www.heracliteanriver.com/?p=324|url-status=live}}</ref> Wider spacing continued to be used by both typesetters and typists until the [[World War II|Second World War]], after which typesetters gradually transitioned to word spacing between sentences in published print, while typists continued the practice of using two spaces.<ref>
{{cite book
 | title= The Complete Manual of Typography: A Guide to Setting Perfect Type
 | last = Felici
 | first= James
 | year = 2003
 | publisher= Peachpit Press
 | location= Berkeley, CA
 | isbn = 0321127307
 | pages= 80
 }};
</ref><ref>{{cite web|url= http://typedesk.com/2011/05/24/the-curious-misconception-surrounding-sentence-spacing/|title= The Curious Misconception Surrounding Sentence Spacing|author= David Spencer|date= 24 May 2011|work= Type Desk|publisher= Matador|access-date= 27 May 2011|archive-date= 10 June 2011|archive-url= https://web.archive.org/web/20110610152438/http://typedesk.com/2011/05/24/the-curious-misconception-surrounding-sentence-spacing/|url-status= live}}</ref><ref>{{cite book
 | title= The Elements of Typographic Style
 | edition= 3
 | last = Bringhurst
 | first= Robert
 | year = 2004
 | publisher= Hartley & Marks
 | location= Washington and Vancouver
 | isbn = 0881792063
 | page = 28
 | quote= 2.1.4 Use a single word space between sentences. In the nineteenth century, which was a dark and inflationary age in typography and type design, many compositors were encouraged to stuff extra space between sentences. Generations of twentieth century typists were then taught to do the same, by hitting the spacebar twice after every period [full stop]. Your typing as well as your typesetting will benefit from unlearning this quaint Victorian habit. As a general rule, no more than a single space is required after a period, colon, or any other mark of punctuation
 }}</ref><ref>{{cite book
 | title= Dynamics in Document Design: Creating Text for Readers
 | edition= 1
 | last = Schriver
 | first= Karen
 | year = 1997
 | publisher= Wiley
 | location= New York
 | isbn = 9780471306368
 | page = 502
 | quote= Use one space (not two) after these punctuation marks [sc. period, question mark, exclamation point, or colon], as the practice of using two spaces is just another holdover from using a typewriter.
 }}</ref><ref>{{cite book
 | title= The Blue Book of Grammar and Punctuation: An Easy-to-Use Guide with Clear Rules, Real-World Examples, and Reproducible Quizzes
 | last= Strauss
 | first= Jane
 | edition= 10
 | year= 2007
 | publisher= Jossey-Bass
 | isbn= 9780470222683
 | pages= 176
 | url= http://www.grammarbook.com/
 | chapter= Spacing with Punctuation
 | chapter-url= http://www.grammarbook.com/punctuation/spacing.asp
 | quote= Rule 1. With a computer, use only one space following periods, commas, semicolons, colons, exclamation points, question marks, and quotation marks. The space needed after these punctuation marks is proportioned automatically. With some typewriters and word processors, follow ending punctuation with two spaces when using a fixed-pitch font.
 | access-date= 2010-04-25
 | archive-date= 2010-04-28
 | archive-url= https://web.archive.org/web/20100428035624/http://www.grammarbook.com/
 | url-status= live
 }}</ref><ref>{{cite book
 |title       = The GPO Style Manual
 |edition     = 30
 |year        = 2008
 |publisher   = The U.S. Government Printing Office
 |location    = Washington
 |isbn        = 9780160818127
 |pages       = 469
 |url         = http://www.gpoaccess.gov/stylemanual/
 |chapter     = 2.49 Leading and spacing
 |chapter-url  = http://frwebgate.access.gpo.gov/cgi-bin/getdoc.cgi?dbname=2008_style_manual&docid=f:chapter2.pdf
 |quote       = A single justified word space will be used between sentences. This applies to all types of composition.
 |access-date  = 2010-04-25
 |url-status     = dead
 |archive-url  = https://web.archive.org/web/20080831023726/http://www.gpoaccess.gov/stylemanual/
 |archive-date = 2008-08-31
}}</ref><ref>{{cite book
 | title= MLA Handbook for Writers of Research Papers
 | edition= 7
 | year= 2009
 | publisher= Modern Language Association
 | isbn= 978-0-87352-297-7
 | pages= 292
 | url= http://www.mla.org/
 | chapter= FAQ: How many spaces should I leave after a period or other concluding mark of punctuation?
 | chapter-url= http://www.mla.org/style_faq3
 | quote= Publications in the United States today usually have the same spacing after a punctuation mark as between words on the same line. Since word processors make available the same fonts used by typesetters for printed works, many writers, influenced by the look of typeset publications, now leave only one space after a concluding punctuation mark. In addition, most publishers' guidelines for preparing electronic manuscripts ask authors to type only the spaces that are to appear in print.
 | access-date= 2010-04-25
 | archive-date= 2011-02-28
 | archive-url= https://web.archive.org/web/20110228040437/http://www.mla.org/
 | url-status= live
 }}</ref><ref>{{cite book
 | title= The Chicago Manual of Style
 | edition= 7
 | year= 2009
 | publisher= University of Chicago Press
 | isbn= 9780873522977
 | pages= 292
 | url= http://www.mla.org/
 | chapter= FAQ: How many spaces should I leave after a period or other concluding mark of punctuation?
 | chapter-url= http://www.mla.org/style_faq3
 | quote= Publications in the United States today usually have the same spacing after a punctuation mark as between words on the same line. Since word processors make available the same fonts used by typesetters for printed works, many writers, influenced by the look of typeset publications, now leave only one space after a concluding punctuation mark. In addition, most publishers' guidelines for preparing electronic manuscripts ask authors to type only the spaces that are to appear in print.
 | access-date= 2010-04-25
 | archive-date= 2011-02-28
 | archive-url= https://web.archive.org/web/20110228040437/http://www.mla.org/
 | url-status= live
 }}</ref><ref>{{cite web
 | title= The Chicago Manual of Style Online (Q&A: One Space or Two?)
 | url= http://www.chicagomanualofstyle.org/
 | year= 2003
 | publisher= University of Chicago Press
 | access-date= 2010-04-25
 | quote= The view at CMOS is that there is no reason for two spaces after a period in published work. Some people, however—my colleagues included—prefer it, relegating this preference to their personal correspondence and notes. I've noticed in old American books printed in the few decades before and after the turn of the twentieth century (ca. 1870–1930 at least) that there seemed to be a trend in publishing to use extra space (sometimes quite a bit of it) after periods. And many people were taught to use that extra space in typing class (I was). But introducing two spaces after the period causes problems: (1) it is inefficient, requiring an extra keystroke for every sentence; (2) even if a program is set to automatically put an extra space after a period, such automation is never foolproof; (3) there is no proof that an extra space actually improves readability—as your comment suggests, it's probably just a matter of familiarity (Who knows? perhaps it's actually more efficient to read with less regard for sentences as individual units of thought—many centuries ago, for example in ancient Greece, there were no spaces even between words, and no punctuation); (4) two spaces are harder to control for than one in electronic documents (I find that the earmark of a document that imposes a two-space rule is a smattering of instances of both three spaces and one space after a period, and two spaces in the middle of sentences); and (5) two spaces can cause problems with line breaks in certain programs. So, in our efficient, modern world, I think there is no room for two spaces after a period. In the opinion of this particular copyeditor, this is a good thing.
 | archive-date= 2009-01-05
 | archive-url= https://web.archive.org/web/20090105172745/http://www.chicagomanualofstyle.org/
 | url-status= live
 }}</ref><ref>{{cite book
 | title= Publication Manual of the American Psychological Association (aka APA Style)
 | edition= 5
 | year= 2001
 | publisher= American Psychological Association
 | location= Washington
 | isbn= 9781557987907
 | pages= [https://archive.org/details/publicationmanua00loom/page/439 439]
 | url= https://archive.org/details/publicationmanua00loom
 | chapter= Chapter 5. Manuscript Preparation and Sample Papers to be Submitted for Publication
 | quote= 5.11 Spacing and Punctuation: Space once after all punctuation as follows: after commas, colons, and semicolons; after punctuation marks at the end of sentences; after periods that separate parts of a reference citation; and after the periods of the initials in personal names (e.g., J. R. Zhang). Exception: Do not use space after internal periods in abbreviations (e.g., a.m, i.e., U.S.)
 | access-date= 2010-04-25
 | url-access= registration
 }}</ref><ref>{{cite book
 | title= Style Manual: for Authors, Editors and Printers (aka AGPS Style)
 | edition= 6
 | year= 2002
 | publisher= Wiley Australia, The Commonwealth Government of Australia Printing Office
 | location= Stafford, Australia
 | isbn= 978-0-7016-3647-0
 | page= 117
 | url= http://australia.gov.au/publications/style-manual
 | quote= In typewritten (as distinct from typeset) material, it was customary to place two spaces after a colon, semicolon, full stop or other sentence closing punctuation. Programs for word processing and desktop publishing offer more sophisticated, variable spacing, so this practice of double spacing is now avoided because it can create distracting gaps on a page.
 | access-date= 2010-04-25
 | archive-date= 2015-03-26
 | archive-url= https://web.archive.org/web/20150326021312/http://www.australia.gov.au/publications/style-manual
 | url-status= dead
 }}</ref>
* One widened space, typically one-and-a-third to slightly less than twice as wide as a word space. This spacing was sometimes used in typesetting before the 19th century. It has also been used in other non-typewriter typesetting systems such as the [[Linotype machine]]<ref>{{cite book |title= Linotype Keyboard Operation: Methods of Study and Procedures for Setting Various Kinds of Composition on the Linotype|last=Mergenthaler Linotype Company|year=1940|publisher=Mergenthaler Linotype Company|ref=Mer40}} cited in {{cite web|url= http://typophile.com/node/3466|title= Double-spacing after Periods|author= Mark Simonson|date= 5 March 2004|work= Typophile|access-date= 5 April 2010|archive-date= 20 January 2010|archive-url= https://web.archive.org/web/20100120091711/http://typophile.com/node/3466|url-status= dead}}</ref> and the [[TeX]] system.<ref>{{citation|last=Eijkhout|first=Victor|title=TeX by Topic, A TeXnician's Reference|url=http://savannah.nongnu.org/files/?group=texbytopic|pages=185–188|year=2008|publisher=Lulu|format=PDF}}{{Dead link|date=June 2023 |bot=InternetArchiveBot |fix-attempted=yes }}<!--Originally published by Addison-Wesley, so it is a RS.--></ref> Modern computer-based digital fonts can adjust the spacing after terminal punctuation as well, creating a [[Sentence spacing#Computer era|space]] slightly wider than a standard word space.<ref>{{cite book |title= The Complete Manual of Typography: A Guide to Setting Perfect Type|last= Felici|first= James|year= 2003|publisher= Peachpit Press|location= Berkeley, CA|isbn= 0-321-12730-7|page= 80}}; {{cite book|title= Grammar Girl's Quick and Dirty Tips for Better Writing (Quick and Dirty Tips)|last= Fogarty|first= Mignon|year= 2008|publisher= Holt Paperbacks|location= New York|isbn= 978-0-8050-8831-1|page= [https://archive.org/details/grammargirlsquic0000foga/page/85 85]|url= https://archive.org/details/grammargirlsquic0000foga/page/85}}; {{cite book |title= The Blue Book of Grammar and Punctuation: An Easy-to-Use Guide with Clear Rules, Real-World Examples, and Reproducible Quizzes|edition=10th|last= Straus|first= Jane|year= 2009|publisher=Jossey-Bass|location= San Francisco, CA|isbn=978-0-470-22268-3|page=52}}</ref>

There has been some [[Sentence spacing#Controversy|controversy]] regarding the proper amount of sentence spacing in typeset material. The ''Elements of Typographic Style'' states that only a single word space is required for sentence spacing.<ref>{{cite book |title= The Elements of Typographic Style|edition= 3.0|last= Bringhurst|first= Robert|year= 2004|publisher= Hartley & Marks|location= Washington and Vancouver|isbn= 0-88179-206-3|pages= 28, 30}}</ref> Psychological studies suggest "readers benefit from having two spaces after periods."<ref>{{cite news|last1=Hamblin|first1=James|title=The Scientific Case for Two Spaces After a Period|url=https://www.theatlantic.com/science/archive/2018/05/two-spaces-after-a-period/559304/|access-date=14 May 2018|work=[[The Atlantic]]|date=11 May 2018|archive-date=14 May 2018|archive-url=https://web.archive.org/web/20180514150447/https://www.theatlantic.com/science/archive/2018/05/two-spaces-after-a-period/559304/|url-status=live}}</ref>

===Unit symbols and numbers===
{{main|International System of Units#Lexicographic conventions}}

The [[International System of Units|International System of Units (SI)]] prescribes inserting a space between a number and a [[unit of measurement]] (the space being regarded as an implied multiplication sign) but never between a prefix and a base unit; a space (or a [[multiplication dot]]) should also be used between units in compound units.<ref name='BIPM style'>{{cite book 
|url= https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf/ 
|title= The International System of Units (SI) 
|author= International Bureau of Weights and Measures 
|author-link= International Bureau of Weights and Measures 
|page= 149 
|year= 2019 
|edition= 9th 
|access-date= 2023-01-13 
|archive-date= 2023-01-13 
|archive-url= https://web.archive.org/web/20230113090424/https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf/ 
|url-status= live 
}}.</ref>
{{plainlist|indent=1|
* 5.0&nbsp;cm, ''not'' {{not a typo|5.0cm}} or {{not a typo|5.0 c m}} or {{not a typo|5.0 cms}}
* 45&nbsp;kg, ''not'' {{not a typo|45kg}} or {{not a typo|45 k g}} or {{not a typo|45 kgs}}
* {{not a typo|32&nbsp;°C}}, ''not'' {{not a typo|32°C}} or {{not a typo|32° C}}
* 20&nbsp;kN&nbsp;m or 20&nbsp;kN⋅m, ''not'' {{not a typo|20 kNm}} or {{not a typo|20 k Nm}}
* π/2&nbsp;rad, ''not'' {{not a typo|π/2rad}} or {{not a typo|π / 2 rad}}
* 50&nbsp;%, ''not'' {{not a typo|50%}} or {{not a typo|50 percent}} (Note: % is not an SI unit, and many [[style guide]]s do not follow this recommendation; {{not a typo|50%}} is used as adjective, e.g. to express concentration as in 50% acetic acid.)
}}
The only exception to this rule is the traditional symbolic notation of [[angle]]s: [[degree (angle)|degree]] (e.g., 30°), [[minute of arc]] (e.g., 22′), and [[second of arc]] (e.g., 8″).

The SI also prescribes the use of a space<ref>{{Cite book|url=https://www.bipm.org/utils/common/pdf/si-brochure/SI-Brochure-9.pdf|title=The International System of Units|edition=9th|publisher=International Bureau of Weights and Measures|year=2019|isbn=978-92-822-2272-0|pages=150|access-date=2019-11-13|archive-date=2021-10-18|archive-url=https://web.archive.org/web/20211018184555/https://www.bipm.org/documents/20126/41483022/SI-Brochure-9.pdf/fcf090b2-04e6-88cc-1149-c3e029ad8232|url-status=live}}</ref> (often typographically a [[thin space]]) as a [[thousands separator]] where required. Both the point and the comma are reserved as [[decimal marker]]s.
{{plainlist|indent=1|
* 1 000 000 000 000 (thin space) or 1000000 ''not'' 1,000,000 or 1.000.000
* 1 000 000 000 000 (regular space which is significantly wider)
}}
{{anchor|Non-breaking space}}Sometimes a [[Non-breaking space#Width variation|narrow non-breaking space]] or [[non-breaking space]], respectively, is recommended (as in, for example, [[IEEE Standards]]<ref>{{Cite web|url=https://standards.ieee.org/wp-content/uploads/import/governance/revcom/scc14.pdf|title=SCC 14 Conventions for Metrication of IEEE Standards|date=2017-10-31|publisher=[[IEEE]]|access-date=2019-11-12|archive-date=2019-07-23|archive-url=https://web.archive.org/web/20190723192955/https://standards.ieee.org/content/dam/ieee-standards/standards/web/governance/revcom/scc14.pdf|url-status=live}}</ref> and [[IEC standards]]<ref>{{Cite web |date=2022-07-18 |title=Writing and formatting {{!}} IEC |url=https://www.iec.ch/standards-development/writing-and-formatting#article-header-id-65fd-usingnon-breakingspacestokeeptextelementstogether |url-status=live |archive-url=https://web.archive.org/web/20220718143708/https://www.iec.ch/standards-development/writing-and-formatting |archive-date=2022-07-18 |access-date=2022-07-18 |website=International Electrotechnical Commission}}</ref>) to avoid the separation of units and values or parts of compounds units, due to automatic [[line wrap and word wrap]].