Wikipedia:Hyphens and dashes

This essay introduces the basics of hyphens, minus signs, en dashes, and em dashes in one easy lesson.

There are at least eight different horizontal dash-like characters of varying lengths defined in Unicode, a character encoding standard. Wikipedia uses four: the hyphen (sometimes called the hyphen-minus), the minus sign, the en dash, and the em dash.

Hyphen (- or -, MOS:HYPHEN; known as the hyphen-minus in ASCII and Unicode) are used in many ways on Wikipedia. They are the only short, horizontal dash-like character available as a separate key on most keyboards. They are used:

• in names, such as "Julia Louis-Dreyfus" and "Sainte-Ode",
• in compound modifiers, as in "hard-boiled egg", "small-appliance industry", and "real-valued function",
• for prefixes and suffixes, such as "mid-Atlantic" and "shell-like",
• when prefixing a capitalized word, such as "un-Christian",
• to avoid double vowels, such as "semi-independent"
• when writing out fractions like "one-third" or "three-fifths"

The hyphen is entered by the hyphen or minus key on all standard keyboards. In mathematical formula templates, a hyphen codes for a minus sign, but in plain text − produces the minus sign (see below).

En dash (– or –, MOS:ENDASH) are slightly longer than hyphens. They are used:

• in date ranges, such as 1849–1863,
• to join two names in a phrase, such as the Michelson–Morley experiment,
• in multi-part prefixes, such as "post–World War II", although for those, either a hyphen or an en dash can be used; British publications use hyphens, and American publications use en dashes.

Spaced en dashes are also used to set aside a phrase – like this – in a sentence; when this is done, it is preferred that a non-breaking space be used before the en dash and a normal one after it:  – .

Em dash (— or —, MOS:EMDASH) are even longer and are used solely to set aside a phrase—like this—in a sentence.

Em dashes and en dashes, when used to set off parentheticals, are interrupters, along with parentheses (round brackets) and commas; the principal differences are that parentheses are used to offset text of an optional or "aside" nature, commas are used to offset text that flows as an integral part of the sentence, and dashes are used to offset text in an emphasized manner.

Minus sign (− or − or {{subst:minus}}, Wikipedia:Manual of Style/Mathematics § Minus sign) are available for negative numbers such as −4 but can cause difficulties in sorts and searches.

In mathematical formulas on Wikipedia,math HTML templates use the hyphen (-) as LaTeX markup inside <math>...</math> to code for a minus sign (see Help:Displaying a formula § LaTeX basics). In HTML plain text, the proper minus sign (−) should be used, and this can be produced using the HTML code −.

In certain writing styles, minus signs are represented using an en dash (–) instead of the proper minus sign (−) or a hyphen (-). However, this practice is not followed in Wikipedia.

Entry of these characters

Main page: Wikipedia:How to make dashes

Since 2014, Wikipedia automatically includes the en dash, em dash, and minus characters in the "Insert" tools below the text-entry field when in editing mode. For those who have turned this feature off in their user preferences, the information below may be used to help generate these characters.

Hyphens ("-") can be used for initial entry of an em dash, en dash, or minus sign, which will be replaced with a more precise form may be done by other subsequent editors. Disrupting Wikipedia to constantly complain about the consensus for the more precise forms can be annoying.

Many computer devices have special key chords (combinations of keys) which can be pressed together to enter various dash characters.

• On computers with Windows XP or Windows 7 (or similar), digits on the numeric keypad can be pressed with the Alt key held then released:

• Numeric keypad: Alt+0150 for en dash "–" or Alt+0151 for em dash "—".

• On computers using Apple keyboards (Mac OS), the Option key can be used with hyphen key:

• Option key: ⌥ Opt+- for en dash "–" or ⇧ Shift+⌥ Opt- for em dash "—".

• On iOS Devices, tap and hold (long press) the - on-screen key to display choices for the en dash "–" and em dash "—".

The four hyphen/dash-like characters used in Wikipedia are:

1. - is a hyphen-minus (ASCII 2D, Unicode 002D), normally used as a hyphen, or in math expressions as a minus sign
2. – is an en dash (Unicode 2013). This can also be entered from the Special characters: Symbols bar above the text-entry field; it's between the m³ and —
3. — is an em dash (Unicode 2014). This can also be entered from the Special characters: Symbols bar; it's between the – and …
4. − is a minus (Unicode 2212). This can also be entered from the Special characters: Symbols bar; it's between the ± and ×

These characters may also be generated with character entity reference codes inserted into wikitext:

• En dash: – a.k.a. – a.k.a. –
• Em dash: — a.k.a. — a.k.a. —
• Minus: − a.k.a. − a.k.a. −

The hyphen-minus can also be generated this way, but this is rarely necessary except for technical reasons in template development:

• Hyphen minus: - a.k.a. -

See also

• WP:Manual of Style, esp. MOS:DASH