| Mark: | / |
| Slash or solidus | |
| Variant1: | ⁄ |
| Caption1: | Fraction slash |
| Variant2: | ∕ |
| Caption2: | Division slash |
| Variant3: | ／ |
| Caption3: | Fullwidth solidus |
The slash is a slanting line punctuation mark . It is also known as a stroke, a solidus, a forward slash and several other historical or technical names. Once used to mark periods and commas, the slash is now used to represent division and fractions, exclusive 'or' and inclusive 'or', and as a date separator.
A slash in the reverse direction is known as a backslash.
Slashes may be found in early writing as a variant form of dashes, vertical strokes, etc. The present use of a slash distinguished from such other marks derives from the medieval European virgule (Latin: virgula, which was used as a period, scratch comma, and caesura mark.[1] (The first sense was eventually lost to the low dot and the other two developed separately into the comma and caesura mark) Its use as a comma became especially widespread in France, where it was also used to mark the continuation of a word onto the next line of a page, a sense later taken on by the hyphen .[2] The Fraktur script used throughout Central Europe in the early modern period used a single slash as a scratch comma and a double slash as a dash. The double slash developed into the double oblique hyphen and double hyphen or before being usually simplified into various single dashes.
In the 18th century, the mark was generally known in English as the "oblique".[3] but particularly the less vertical fraction slash.[4] The variant "oblique stroke" was increasingly shortened to "stroke", which became the common British name for the character, although printers and publishing professionals often instead referred to it as an "oblique". In the 19th and early 20th century, it was also widely known as the "shilling mark" or "solidus", from its use as a notation or abbreviation for the shilling.[5] [6] The name "slash" is a recent development, not appearing in Webster's Dictionary until the Third Edition (1961)[7] but has gained wide currency through its use in computing, a context where it is sometimes used in British English in preference to "stroke". Clarifying terms such as "forward slash" have been coined owing to widespread use of Microsoft's DOS and Windows operating systems, which use the backslash extensively.[8] [9]
See also: Gender neutrality in languages with grammatical gender. The slash is commonly used in many languages as a shorter substitute for the conjunction "or", typically with the sense of exclusive or (e.g., Y/N permits yes or no but not both).[10] Its use in this sense is somewhat informal,[11] although it is used in philology to note variants (e.g., virgula/) and etymologies (e.g., F. French: virgule/LL. Latin: virgula/L. Latin: virga/PIE. ).
Such slashes may be used to avoid taking a position in naming disputes. One example is the Syriac naming dispute, which prompted the US and Swedish censuses to use the respective official designations "Assyrian/Chaldean/Syriac" and "Assyrier/Syrianer" for the ethnic group.
In particular, since the late 20th century, the slash is used to permit more gender-neutral language in place of the traditional masculine or plural gender neutrals. In the case of English, this is usually restricted to degendered pronouns such as "he/she" or "s/he". Most other Indo-European languages include more far-reaching use of grammatical gender. In these, the separate gendered desinences (grammatical suffices) of the words may be given divided by slashes or set off with parentheses. For example, in Spanish, Spanish; Castilian: hijo is a son and a Spanish; Castilian: hija is a daughter; some proponents of gender-neutral language advocate the use of Spanish; Castilian: hijo/a or Spanish; Castilian: hijo(a) when writing for a general audience or addressing a listener of unknown gender.[12] [13] [14] Less commonly, at sign is used instead: Spanish; Castilian: hij@. Similarly, in German and some Scandinavian and Baltic languages, German: Sekretär refers to any secretary and German: Sekretärin to an explicitly female secretary; some advocates of gender neutrality support forms such as German: Sekretär/-in for general use. This does not always work smoothly, however: problems arise in the case of words like German: Arzt ('doctor') where the explicitly female form German: Ärztin is umlauted and words like German: Chinese ('Chinese person') where the explicitly female form German: Chinesin loses the terminal -e.
The slash is also used as a shorter substitute for the conjunction "and" or inclusive or (i.e., A or B or both), typically in situations where it fills the role of a hyphen or en dash. For example, the "Hemingway/Faulkner generation" might be used to discuss the era of the Lost Generation inclusive of the people around and affected by both Hemingway and Faulkner. This use is sometimes proscribed, as by New Hart's Rules, the style guide for the Oxford University Press.
The slash, as a form of inclusive or, is also used to punctuate the stages of a route (e.g., Shanghai/Nanjing/Wuhan/Chongqing as stops on a tour of the Yangtze).
The word slash is also developing as a way to introduce topic shifts or follow-up statements. Slash can introduce a follow-up statement, such as, "I really love that hot dog place on Liberty Street. Slash can we go there tomorrow?" It can also indicate a shift to an unrelated topic, as in "JUST SAW ALEX! Slash I just chubbed on oatmeal raisin cookies at north quad and i miss you." The new usage of "slash" appears most frequently in spoken conversation, though it can also appear in writing.[15]
Sometimes the word slash is used in speech as a conjunction to represent the written role of the character (as if a written slash were being read aloud from text), e.g. "bee slash mosquito protection" for a beekeeper's net hood,[16] and "There's a little bit of nectar slash honey over here, but really it's not a lot." (said by a beekeeper examining in a beehive),[17] and "Gastornis slash Diatryma" for two supposed genera of prehistoric birds which are now thought to be one genus.[18]
The fraction slash is used between two numbers to indicate a fraction or ratio. Such formatting developed as a way to write the horizontal fraction bar on a single line of text. It is first attested in England and Mexico in the 18th century.[19] This notation is known as an online, solidus,[20] or shilling fraction. Nowadays fractions, unlike inline division, are often given using smaller numbers, superscript, and subscript (e.g., ⁄). This notation is responsible for the current form of the percent, permille, and permyriad signs, developed from the horizontal form which represented an early modern corruption of an Italian abbreviation of per cento.[21]
Many fonts draw the fraction slash (and the division slash) less vertical than the slash. The separate encoding is also intended to permit automatic formatting of the preceding and succeeding digits by glyph substitution with numerator and denominator glyphs (e.g., display of "1, fraction slash, 2" as "½"),[22] though this is not yet supported in many environments or fonts. Because of this lack of support, some authors still use Unicode subscripts and superscripts to compose fractions, and many fonts design these characters for this purpose. In addition, all of the multiples less than 1 of ⁄ for 2 ≤ n ≤ 6 and n = 8 (e.g. ⁄ and ⁄), as well as ⁄, ⁄, and ⁄, are in the Unicode Number Forms or Latin-1 Supplement block as precomposed characters.[23]
This notation can also be used when the concept of fractions is extended from numbers to arbitrary rings by the method of localization of a ring.
The division slash, equivalent to the division sign, may be used between two numbers to indicate division. For example, can also be written as . This use developed from the fraction slash in the late 18th or early 19th century. The formatting was advocated by De Morgan in the mid-19th century.[24]
See also: Set (mathematics). A quotient of a set is informally a new set obtained by identifying some elements of the original set. This is denoted as a fraction
S/R
S
\sim
S
S/{\sim}
\sim
S/{\sim}
\sim
In group theory, the slash is used to mark quotient groups. The general form is
G/N
G
N
G
N
g\simh
g=hn
n\inN
When the original set is the set of integers
Z
Z/n
Zn
Zn
Z/n
Z/nZ
Z/(n)
Slashes may also be used as a combining character in mathematical formulae. The most important use of this is that combining a slash with a relation negates it, producing e.g. 'not equal'
≠
=
\notin
\in
\nmid
\mid
\nsim
\sim
The Feynman slash notation is an unrelated use of combining slashes, mostly seen in quantum field theory. This kind of combining slash takes a vector base symbol and converts it to a matrix quantity. Technically this notation is a shorthand for contracting the vector with the Dirac gamma matrices, so
A/=\gamma\muA\mu
The slash, sometimes distinguished as "forward slash", is used in computing in a number of ways, primarily as a separator among levels in a given hierarchy, for example in the path of a filesystem.
The slash is used as the path component separator in many computer operating systems (e.g., Unix's). In Unix and Unix-like systems, such as macOS and Linux, the slash is also used for the volume root directory (e.g., the initial slash in). Confusion of the slash with the backslash largely arises from the use of the latter as the path component separator in the widely used MS-DOS and Microsoft Windows systems.
The slash is used in a similar fashion in internet URLs (e.g.,