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In computer-based text processing and digital typesetting, a non-breaking space or no-break space (NBSP) is a variant of the space character that prevents an automatic line break (line wrap) at its position. In certain formats (such as HTML) it also prevents the "collapsing" of multiple consecutive whitespace characters into a single space. The non-breaking space is also known as a hard space or fixed space. In HTML and wikitext a non-breaking space is created by replacing the space with . This is a non-breaking space: " "
Non-breaking behavior[]
Text-processing software typically assumes that an automatic line break may be inserted anywhere a space character occurs; a non-breaking space prevents this happening (provided the software recognizes the character, of course). 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". To avoid this undesirable behaviour, the editor 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.
Use as non-collapsing white-space[]
A second common application of non-breaking spaces is in plain text file formats such as SGML, HTML, TeX and LaTeX which sometimes treat sequences of whitespace characters (space, newline, tab, form feed, etc.) as if they were a single white-space character. Such "collapsing" of white-space allows the author to neatly arrange the source text using line breaks, indentation and other forms of spacing without affecting the final typeset result.
In contrast, non-breaking spaces are not merged with neighboring whitespace characters, and can therefore be used by an author to insert additional visible space in the formatted text. For example, in HTML, non-breaking spaces may be used in conjunction with a fixed-width font to create tabular alignment:
Column 1 Column 2
-------- --------
1.2 2.3
(notice that the use of the pre tag, the whitespace:pre CSS rule, or a table are alternative, if not better ways to achieve the same result in HTML)
If ordinary spaces are used instead then the spaces are collapsed when the HTML is rendered and the layout is broken:
Column 1 Column 2
-------- --------
1.2 2.3
Encodings[]
| Format | Representation of non-breaking space |
|---|---|
| Unicode and ISO/IEC 10646 | U+00A0. This can be encoded by UTF-8 as 0xC2 0xA0. |
| ISO/IEC 8859 | 0xA0 |
| CP1252 (windows default) | 0xA0 |
| KOI8-R | 0x9A |
| EBCDIC | 0x41 |
| CP437 and CP850 | 0xFF |
| SGML and HTML (including Wikitext) | Character entity reference: Numeric character references:   or  
|
| TeX | tilde (~) |
| ASCII | Not available |
Unicode defines several other non-break space characters that differ from the regular space in width:
- No-break thin space, known in Unicode as "NARROW NO-BREAK SPACE" (U+202F). This is required for French punctuation (before ?, ! or ;).
- Word joiner, encoded in Unicode 3.2 and above as U+2060. The word-joiner does not normally produce any space but prohibits a line break on either side of it.
- The Byte Order Mark, U+FEFF, officially named "ZERO WIDTH NO-BREAK SPACE", can also be used with the same meaning as the word joiner, but in current documents this use is deprecated. See also Zero-width non-breaking space.
Keyboard entry methods[]
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 the SFS setting, the non-breaking space can be entered with the key combination AltGr + Space.[1]
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 |
|---|---|
| Mac OS | Option+Space |
| X11 | Compose, Space, Space |
| Emacs | Ctrl+X 8 Space |
| Vim | Ctrl+K N S |
| Windows (all applications) | Alt+0160 or Alt+255 (on numeric keypad) |
| Microsoft Word, Dreamweaver, OpenOffice.org (since 3.0) |
Ctrl+Shift+Space |
| WordPerfect, OpenOffice.org (before 3.0), LyX | Ctrl+Space, Ctrl+Shift+Space for recent OpenOffice (see LP) |
| GTK-based applications | Ctrl+Shift+U 00A0 |
| Mac Adobe InDesign | Option+Command+X |
| Many office applicationsTemplate:Vague | Insert → Symbol dialog box (Latin-1 subset, after ~) |
See also[]
- Space (punctuation), symbol "Word Joiner"
- Byte order mark, formerly known as "zero width no-break space"
- Punctuation
- Hyphens in computing, for information about hard and non-breaking hyphens
- List of XML and HTML character entity references
- Sentence spacing in the digital age
References[]
- ↑ Kotoistus: Uusi näppäinasettelu = Status of the new Keyboard Layout. A bi-lingual (Finnish + English) presentation page collecting drafts of the Finnish Multilingual Keyboard. CSC – IT Center for Science Ltd. (Page updated 2006-12-28.)
cs:Nezlomitelná mezera de:Geschütztes Leerzeichen es:Espacio duro fr:Espace insécable ko:단어 잘림 방지 공백 it:Hard space ja:ノーブレークスペース no:Non-breaking space nn:Hardt mellomrom pl:Spacja niełamliwa pt:Espaço rígido ru:Пробел#Неразрывный пробел fi:Sitova välilyönti sv:Hårt mellanslag