Hyphen-minus
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Hyphen-minus | |
The hyphen-minus (-) is a character used in digital documents and computing to represent a hyphen (‐) or a minus sign (−).[1]
It is present in Unicode as code point U+002D - HYPHEN-MINUS; it is also in ASCII with the same value.
Description
The use of a single character for both hyphen and minus was a compromise made in the early days of fixed-width typewriters and computer displays.[2] However, in proper typesetting and graphic design, there are distinct characters for hyphens, dashes, and the minus sign. Usage of the hyphen-minus nonetheless persists in many contexts, as it is well-known, easy to enter on keyboards, and in the same location in all common character sets.
As the minus sign
Most programming languages, restricting themselves to 7-bit ASCII, use the hyphen-minus, rather than the Unicode character U+2212 − MINUS SIGN, for denoting subtraction and negative numbers.[3][4]
The minus sign is nominally the same width as the plus sign. In proportional typefaces it is longer than a hyphen. During typesetting a word wrap may also occur following a hyphen-minus, unlike the minus sign proper which is treated as a mathematical symbol. These differences make "-" as a substitute for minus signs undesirable in professional typography.
Other uses
On typewriters, it was conventional to use a pair of hyphens to represent an em dash, and this convention is still sometimes used in computer text.
The hyphen-minus is often used to represent an en dash, which may be used to indicate ranges (such as a time range of "2000–2004"), direction (as in "The Los Angeles–London flight"), and other cases of connection. The en dash is normally longer (the width of a letter "n") than a hyphen, though in a fixed-pitch or typewriter font there is no difference. The hyphen connects closely, the en dash less closely, while the em dash (the width of a letter "m") separates.[5]
See also
- -- (disambiguation)
- Soft hyphen
The dictionary definition of - at Wiktionary
References
- ↑ Jukka K. Korpela (2006). Unicode explained. O'Reilly. p. 382. ISBN 978-0-596-10121-3.
- ↑ Fischer, Eric. "The Evolution of Character Codes, 1874-1968" (PDF). Retrieved 2016-11-16.
- ↑ Ritchie, Dennis (c. 1975). "C Reference Manual" (PDF). Retrieved 2016-12-07.
- ↑ "Haskell 2010 Language Report" (PDF). Retrieved 2016-12-07.
- ↑ "Hyphens, En Dashes, Em Dashes". The Chicago Manual of Style Online. Retrieved 25 January 2017.