Wikipedia:Manual of Style (dashes)
From Wikipedia, the free encyclopedia
 |
This page is part of the Manual of Style, and is considered a guideline for Wikipedia. The consensus of many editors formed the conventions described here, and Wikipedia articles should heed these guidelines. Before making any major changes to these guidelines, please use the discussion page to ensure that your changes reflect consensus. |
Wikipedia should use standard rules of English punctuation for dashes. However, some current or future automated Wiki tools make it important to understand how to represent these dashes.
True dashes convey semantic meaning the hyphen lacks, and some feel it makes the rendered text easier to read. They may not display consistently in all browsers. (Please see the talk page.)
Now that Wikipedia uses UTF-8, these can be entered directly into the article markup. To enter an em dash or an en dash after your cursor, for instance, you can click the "—" or "–" link, respectively, below the edit box. See Help:Special characters.
Contents |
[edit] Dashes and hyphens used on Wikipedia
The hyphen, or more accurately the hyphen-minus (-),[1] is the shortest dash-like character visually. Traditionally, this was used only for hyphenating words, creating line breaks, or as the minus sign. For historical reasons, it is the only dash-like character on the keyboard. (Typewriters used two hyphens to render a regular dash.) Dashes have been implemented in various ways that do not display consistently in all software, leading the hyphen to be used in place of dashes.
The minus sign or figure dash (−) is designed to be the same width and height as a plus or equals sign, and should be used in non-TeX equations or to designate negative numbers. It is supported in almost all browsers, and can be used in Wikipedia. Unlike the hyphen, most browsers will not break a line between the minus sign and the associated negative number. It is possible to use the HTML entity − or the numeric form −.
The en dash (–) is slightly longer than a hyphen or a figure dash and about half the width of an em dash. In any font, an en dash is approximately equal in length to the capital "N". It may indicate duration, such as when you could substitute the word "to" (as in a range of dates). An en dash placed between numbers or in compounds does not have spaces around it: for example, Paris–Brussels timetable, in the age range 17–20. Some writers, however, prefer to place a space on either side in complex ranges: 1 January 2003 – 31 December 2004. The en dash can be used as a hyphen in compound adjectives in which one part consists of two or more words or a hyphenated word: for example, New York–London flight, post–Anglo-Saxon times; and it is used in compound adjectives referring to multiple people, so as to clarify that for example the name of the Poincaré–Birkhoff–Witt theorem refers to three people while the Birch–Swinnerton-Dyer conjecture refers to two (one of them called Swinnerton-Dyer). The Guide for the Use of the International System of Units (SI) recommends that the word "to" be used instead of an en dash when a number range might be misconstrued as subtraction, such as a range of units.
The en dash is supported in almost all browsers, and can be used in Wikipedia. Use the HTML entity – (not the numeric form –; see below) or type it in directly if your keyboard allows it. In the house styles of many publishers (two examples: Penguin and Routledge), spaced en dashes are also used instead of em dashes (see next paragraph, and Guidelines below). This is acceptable in Wikipedia; consistency within an article is the most important consideration.
The em dash (—) is twice as long as an en dash, and about the length of the capital "M" in any particular font. The em dash is used in much the same way as a colon or set of parentheses—it can show an abrupt change in thought or be used where a period is too strong and a comma too weak. An em dash can have spaces on either side or not, depending on the writer's preference or in-house style rules. Many writers prefer to use the en dash (spaced) for this parenthetical use, with many of those also preferring a spaced en dash as a colon substitute. Em dashes are sometimes used incorrectly to separate lists of items from their definitions. (A colon should be used instead. Wikipedia also has a defined syntax for definitions, which is often preferable to colons. See How to edit for details.)
The em dash is supported in almost all browsers, and can be used in Wikipedia. Use the HTML entity —, which the MediaWiki engine automatically converts into a numeric entity in the rendered HTML. The numeric entities, — and —, should be avoided in the wikitext: they produce the same result in the rendered HTML, but are more difficult for editors to interpret. You may also type an em dash directly if your keyboard allows it.
Some Wikipedians use a double hyphen (--) to represent an em dash. This is a carryover from typewriter usage, where the double hyphen was used because the typewriter did not have an em dash. The double hyphen was never used in typography because type fonts, like the digital fonts used on computers, always have em dashes.
See also Dash (punctuation) for detailed discussion of usage and more dashes.
[edit] Dashes not used on Wikipedia
The figure dash[2] Unicode character ("‒") should not be used on Wikipedia because browser support for it is lacking in some combinations of operating system, browser and font. Use a hyphen in the Wikipedia instead. It is slightly longer than the hyphen, usually the same length as the en dash. It is the same width as a number, and is used in telephone numbers (e.g. 012‒3456‒7890), to indicate a missing value in numeric data, etc. It can be typed with the numeric form ‒.
The quotation dash ("―") should not be used on Wikipedia. This dash is used to introduce quoted text. If rendered at all, in most fonts it is rendered identically to the em dash. On some systems it can be typed only with the numeric form, ―. Since browser support for it is currently limited, use the em dash in Wikipedia instead.
The following are not dashes:
- The macron ("¯") is a diacritic mark. Do not use it as a dash.
- The underscore or lowline ("_") is another diacritic mark in some languages. It is also used as a non-breaking space or as a space replacement in some computer operating systems. Do not use it as a dash.
[edit] Dash guidelines for Wikipedia editors
Simply click the dash buttons below the edit window, or insert the dash with any software supporting these punctuations. If possible, avoid typing their related codes (e.g., – for en dash) to display dashes, as this clutters the text when editing and may not be understood by new editors.
As with any guideline that permits multiple styles, editors are encouraged not to convert others' dash styles without good reason. However, a significant number of editors feel that to maintain a respectable feel, Wikipedia should use only traditional dash styles; many advocate changing hyphen-based dash styles (a legacy of the days of typewriters and early computers, when true dashes were hard to produce) to more traditional styles based on en and em dashes. Others, however, dispute this, either because they prefer the look of hyphens, think traditional dashes are too ugly or confusing in the edit box, or fear that conflict will arise if editors change each other's styles. A moderate approach is only to change the style of dashes where this is required for consistency within an article.
The following five dash styles are currently in use on Wikipedia:
- Tight (unspaced) em dashes—like this. Entered by means of
—, or, if your keyboard allows it, you can type it in directly, or you can retrieve it from below the edit window (as discussed above). - Spaced em dashes — like this.
- Spaced en dashes – like this. Entered by means of
–, directly if your keyboard allows it, or retrieved from below the edit window. (Note: an unspaced en dash is properly used to indicate a range of numbers; unspaced en dashes should not be used for the parenthetical or colon-type uses, as discussed above.) - A pair of hyphens -- either spaced or unspaced--like that, in place of an em dash. These are simple to type, but are regarded as ugly by some; many feel that an editor who wishes to may freely convert them to em dashes or spaced en dashes. (This may be taken care of in the future by the software.) Most agree that editors who do not want to bother using the em dash character below the edit box may keyboard their em dashes in this fashion; the only dispute whether other editors should change them.
- A single spaced hyphen - like this, in place of a spaced en dash or em dash. Like a double hyphen, this is not traditional, and a substantial number of Wikipedians favor changing them to spaced en dashes (or to em dashes) on sight.
Some editors who use spaced dashes include a non-breaking space before the dash: with — for an em dash; or with – for an en dash. This keeps dashes from appearing at the start of a line. (A very rare variant of this style separates the dash from the surrounding words using hair spaces; since many browsers cannot display hair spaces, these may appear on the display as simple tight dashes. See warnings in what follows.)
For page names:
- Hyphens and dashes are generally rather avoided in page names (e.g., year of birth and death are generally not used in a page name to disambiguate two people with the same name).
- If hyphens and dashes are needed to write a page name correctly (e.g., Piano-Rag-Music, Jack-in-the-box, Nineteen Eighty-Four), prefer simple hyphens, and avoid hair spaces, even in the odd case of a range forming part of the title, e.g., History of the Soviet Union (1985-1991).
If for greater precision another type of dash is used, always provide a redirect from the variant with simple hyphens and without hair spaces.
[Guideline change 14:14, 15 January 2007 (UTC), see talk page:]
Please do not use an en dash, em dash, or any type of dash other than a standard hyphen in a content page name because such symbols prevent some software (including Internet Explorer 6 on Windows XP) from saving the page as a file on a computer. The non-hyphen dashes can be used in redirect pages if an enhanced precision for the page name is desired for use in wikilinks elsewhere.
[edit] Dashes on keyboards
The standard U.S. 101 key keyboard layout does not provide dedicated keys for entering dashes and other typographic punctuation signs missing from ASCII. However, some operating systems have extended these standards and some permit users to customize the keyboard layout. Many Wikipedia editors find that customizing their keyboard to provide additional Unicode characters is by far the most convenient and efficient method of entering them.
[edit] Macintosh
The U.S. English keyboard layout on all Macintosh computers (since 1984) allows a user to type dashes:
- en dash: option-hyphen
- em dash: option-shift-hyphen
[edit] Windows
Under Microsoft Windows, various special characters can be entered by holding down the Alt key while typing a sequence of four digits on the numeric keypad. For dashes, these digits are:
- en dash: alt-0-1-5-0
- em dash: alt-0-1-5-1
[edit] X Window System
Under recent versions of X11, you can obtain the em dash (—) by pressing the Compose key followed by - - - (triple hyphen-minus), and the en dash (–) can be obtained by pressing the Compose key followed by - - . (hyphen-minus, hyphen-minus, dot).
[edit] Notes
- ^ Note: Technically, in the Unicode table, hyphen means U+2010 HYPHEN (‐), not U+002D HYPHEN-MINUS. However, in this page, the word hyphen always means U+002D HYPHEN-MINUS. For example, "use a hyphen instead" would mean "use U+002D" (not U+2010). You can use the "real" hyphen instead of the hyphen-minus as
‐, but some browsers may not display it properly. The same is true about U+2011 NON-BREAKING HYPHEN (‑) or‑. - ^ Note: Distinct from the "minus sign" or "figure dash" mentioned above.
