Hyphen-minus
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Hyphen-minus | |
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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.
The use of one character for hyphen and minus, and sometimes also for en dash, was a compromise made in the early days of fixed-width typewriters and computer displays. 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.
Most programming languages, restricting themselves to ASCII, use the hyphen-minus, rather than the Unicode character U+2212 − MINUS SIGN, for denoting subtraction and negative numbers.
The en-dash is historically a dash of the same width as a lowercase letter "n". The en-dash indicates ranges, such as 2000–2004, and compound adjectives, as in "Italian–American relations" (having to do with the relationship between Italy and America), as opposed to "Italian-American relations" (indicating relatives who are Americans of Italian descent). Hyphen-minuses are often used instead of en-dashes in these cases, but this practice generally stems from ignorance of the en-dash and is not preferred.
Historically, an em dash is the width of a lowercase letter "m", and may be represented by three hyphen-minus signs in succession (as later in TeX markup), or sometimes two.
See also
References
- ↑ Jukka K. Korpela (2006). Unicode explained. O'Reilly. p. 382. ISBN 978-0-596-10121-3.