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Non-breaking space

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Non-breaking space
U+00A0   NO-BREAK SPACE ( ,  )
See also
U+202F NARROW NO-BREAK SPACE

U+0020   SPACE[a][b]

Other types of spaces

In word processing and digital typesetting, a non-breaking space ( ), also called NBSP, required space,[1] hard space, or fixed space (in most typefaces, it is not of fixed width), is a space character that prevents an automatic line break at its position. In some formats, including HTML, it also prevents consecutive whitespace characters from collapsing into a single space. Non-breaking space characters with other widths also exist.

Uses and variations

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Despite having layout and uses similar to those of whitespace, it differs in contextual behavior.[2][3]

Non-breaking behavior

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Text-processing software typically assumes that an automatic line break may be inserted anywhere a space character occurs; a non-breaking space prevents this from happening (provided the software recognizes the character). For example, if the text "100 km" will not quite fit at the end of a line, the software may insert a line break between "100" and "km". An editor who finds this behavior undesirable may choose to use a non-breaking space between "100" and "km". This guarantees that the text "100 km" will not be broken: if it does not fit at the end of a line, it is moved in its entirety to the next line.

Non-collapsing behavior

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A second common application of non-breaking spaces is in plain text file formats such as SGML, HTML, TeX and LaTeX, whose rendering engines are programmed to treat sequences of whitespace characters (space, newline, tab, form feed, etc.) as if they were a single character (but this behavior can be overridden). Such "collapsing" of whitespace allows the author to neatly arrange the source text using line breaks, indentation and other forms of spacing without affecting the final typeset result.[4][5]

In contrast, non-breaking spaces are not merged with neighboring whitespace characters when displayed. They can, therefore, be used by an author to simply insert additional visible space in the resulting output without using spans styled with peculiar values of the CSS "white-space" property. Conversely, indiscriminate use (see the recommended use[citation needed] in style guides), in addition to a normal space, gives extraneous space in the output.

Width variation

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Other non-breaking variants, defined in Unicode:

U+202F NARROW NO-BREAK SPACE (NNBSP)
Due to the tighter binding of value and unit as a continuous visual element NNBSP is recommended for usage in the SI-standard.[6] It was introduced in Unicode 3.0 for Mongolian,[7] to separate a suffix[8] from the word stem without indicating a word boundary. It is also required for big punctuation (sometimes inaccurately referred to as "double punctuation") in French where it is called espace fine insécable (before ;, ?, !, », and after «, ; today often (i.e. in French DTP, referred to[9] as new-school) also before :) and in German between multi-part abbreviations (e.g., "z. B.", "d. h.", "v. l. n. r.").[10] When used with Mongolian, its width is usually one third of the normal space; in other contexts, its width is about 70% of the normal space but may resemble that of the thin space (U+2009), at least with some fonts.[11] Also, starting from release 34 of Unicode Common Locale Data Repository (CLDR), the NNBSP is used in numbers as a group separator in French,[12] and starting from release 44,[13] in Venetian.[14] Spanish is prone to do the same.[15]
U+2007 FIGURE SPACE ( )
Produces a space equal to the figure (0–9) characters.
U+2060 WORD JOINER (⁠ · WJ)
Encoded in Unicode since version 3.2. The word joiner does not produce any space and prohibits a line break at its position.

Example

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On browsers, resizing the window will demonstrate the effect of non-breaking spaces on the texts below.

To show the non-breaking effect of the non-breaking space, the following words have been separated with non-breaking spaces:

Lorem Ipsum Dolor Sit Amet Consectetur Adipiscing Elit Sed Do Eiusmod Tempor Incididunt Ut Labore Et Dolore Magna Aliqua Ut Enim Ad Minim Veniam Quis Nostrud Exercitation Ullamco Laboris Nisi Ut Aliquip Ex Ea Commodo Consequat Duis Aute

To show the non-collapsing behavior of the non-breaking space, the following words have been separated with an increasing number of non-breaking spaces:

Lorem Ipsum  Dolor   Sit    Amet     Consectetur      Adipiscing       Elit        Sed         Do          Eiusmod           Tempor            Incididunt             Ut              Labore               Et                Dolore                 Magna                  Aliqua                   Ut                    Enim                     Ad                      Minim

In contrast, the following words are separated with ordinary spaces:

Lorem Ipsum Dolor Sit Amet Consectetur Adipiscing Elit Sed Do Eiusmod Tempor Incididunt Ut Labore Et Dolore Magna Aliqua Ut Enim Ad Minim Veniam Quis Nostrud Exercitation Ullamco Laboris Nisi Ut Aliquip Ex Ea Commodo Consequat Duis Aute

Here, they are separated with narrow non-breaking spaces, to show the width of those:

Lorem Ipsum Dolor Sit Amet Consectetur Adipiscing Elit Sed Do Eiusmod Tempor Incididunt Ut Labore Et Dolore Magna Aliqua Ut Enim Ad Minim Veniam Quis Nostrud Exercitation Ullamco Laboris Nisi Ut Aliquip Ex Ea Commodo Consequat Duis Aute

Encodings

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Character information
Preview  
Unicode name NO-BREAK SPACE FIGURE SPACE NARROW NO-BREAK SPACE WORD JOINER
Encodings decimal hex dec hex dec hex dec hex
Unicode 160 U+00A0 8199 U+2007 8239 U+202F 8288 U+2060
UTF-8 194 160 C2 A0 226 128 135 E2 80 87 226 128 175 E2 80 AF 226 129 160 E2 81 A0
Numeric character reference             ⁠ ⁠
Named character reference  ,     ⁠
ISO/IEC 8859 (1–16) / ECMA-94 160 A0
Windows code pages: 1250, 1251, 1252, 1253, 1254, 1255, 1256, 1257, 1258 160 A0
KOI8-R, KOI8-U 154 9A
DOS code pages: 437, 850, 851, 852, 853, 855, 856, 857, 858, 859, 860, 861, 862, 863, 864, 865, 866, 867, 869 255 FF
HP Roman-8, HP Roman-9 160 A0
LICS 154 9A
TeX ~ \phantom{9} \, \nobreak
EBCDIC hex: 41 – RSP, Required Space

In Unicode, the byte order mark (BOM), U+FEFF, may be interpreted as a "zero width no-break space", but is a deprecated alternative to word joiner (U+2060).

Keyboard entry methods

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It is rare for national or international standards on keyboard layouts to define an input method for the non-breaking space. An exception is the Finnish multilingual keyboard, accepted as the national standard SFS 5966 in 2008. According to SFS 5966, the non-breaking space can be entered with the key combination AltGr + Space.[16]

Typically, authors of keyboard drivers and application programs (e.g., word processors) have devised their own keyboard shortcuts for the non-breaking space. For example:

System/application Entry method
Microsoft Windows Alt+0160 or Alt+255 (does not always work)
macOS Opt+Shift+Space
Linux or Unix using X11 Compose, Space, Space or AltGr+Space
AmigaOS Alt+Space
GNU Emacs Ctrl+X 8 Space
Vim Ctrl+K, Space, Space; or Ctrl+K, ⇧ Shift+N, ⇧ Shift+S
Dreamweaver, LibreOffice, Microsoft Word,
OpenOffice.org (since 3.0), AutoCAD
Ctrl+⇧ Shift+Space[c]
FrameMaker, LyX (non-Mac), OpenOffice.org (before 3.0),
WordPerfect
Ctrl+Space
Mac Adobe InDesign ⌥ Opt+⌘ Cmd+X
Python programming language '\N{NO-BREAK SPACE}'[17] or '\xa0'/'\u00a0'

Apart from this, applications and environments often have methods of entering unicode entities directly via their code point, e.g., via the Alt Numpad input method. (Non-breaking space has code point 255 decimal (FF hex) in codepage 437 and codepage 850 and code point 160 decimal (A0 hex) in codepage 1252.)

See also

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Notes

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  1. ^ For presentation reasons, representations of a regular space in this article are replaced with a no-break space
  2. ^ Copy/pasting the symbol shown here will result in the light blue color being transferred along with the symbol. This can be avoided by using one of the techniques described at § Keyboard entry methods.
  3. ^ On Windows 10 systems, Ctrl+⇧ Shift will by default switch keyboard configurations if more than one keyboard has been configured for the current language.

References

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  1. ^ IBM (1998) [1995]. "Windows, Latin 1". REGISTRY, Graphic Character Sets and Code Pages. CPGID 01252.
  2. ^ Elyaakoubi, Mohamed; Lazrek, Azzeddine (2010). "Justify Just or Just Justify". The Journal of Electronic Publishing. 13. doi:10.3998/3336451.0013.105. hdl:2027/spo.3336451.0013.105.
  3. ^ "Special Characters". The Chicago Manual of Style Online.
  4. ^ "Structure", HTML 4.01, W3, 1999-12-24.
  5. ^ "Text", CSS 2.1, W3.
  6. ^ "SI-Standard mentioning the insertion of non-breaking space between value and unit" (PDF).
  7. ^ ISO/IEC 10646-1:1993/FDAM 29:1999(E)
  8. ^ "Mongolian NNBSP-connected suffixes" (PDF). W3. December 28, 2014.
  9. ^ claude72 (2005-04-25). "Typo : caractères capitales accentués". Forum App Store et applications > Applications Mac > Création graphique. MacGeneration. p. 5. Retrieved 2019-03-30.{{cite web}}: CS1 maint: numeric names: authors list (link)
  10. ^ Solbrig, Amelie (30 January 2008). "Zweisprachige Mikrotypografie" (PDF) (in German). Hochschule für Technik, Wirtschaft und Kultur Leipzig. p. 58 (PDF p. 113). Archived from the original (PDF) on 2016-03-11. Retrieved 10 June 2018. Alle Abkürzungen mit Binnenpunkten werden im Deutschen mit einem gFL [geschütztes flexibles Leerzeichen] spationiert. [...] Die englische Schreibweise sieht keine Abstände zwischen einzelnen Buchstaben vor. Nach einem Binnenpunkt folgt demnach ohne gFL sofort der nächste Buchstabe.
  11. ^ "Writing Systems and Punctuation" (PDF). The Unicode Standard 7.0. Unicode Inc. 2014. Retrieved 2014-11-02.
  12. ^ "CLDR 34 release note".
  13. ^ "CLDR 44 release note".
  14. ^ "CLDR v44.0 — By-Type Chart: Numbers:Symbols".
  15. ^ RAE; RAE. "punto | Diccionario panhispánico de dudas". «Diccionario panhispánico de dudas» (in Spanish). Retrieved 2022-01-07.
  16. ^ Kotoistus (2006-12-28), Uusi näppäinasettelu [Status of the new keyboard layout] (presentation) (in Finnish and English), CSC – IT Center for Science, archived from the original on 2011-07-27{{citation}}: CS1 maint: location missing publisher (link). Drafts of the Finnish multilingual keyboard.
  17. ^ Python Software Foundation. "Unicode HOWTO¶". Python 3.10.6 documentation. Retrieved 19 August 2022.