Wikipedia:Manual of Style 

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The Manual of Style, often abbreviated MoS, is a style guide for Wikipedia articles. This article contains basic principles. The menu to the right contains links to Manual of Style articles that explore topics in detail. If the Manual of Style does not specify a preferred usage, discuss your issues on the talk page of this article.

Contents

General principles

Internal consistency

An overriding principle on Wikipedia is that style and formatting should be applied consistently within articles, though not necessarily throughout the encyclopedia as a whole. One way of presenting information may be as good as another, but consistency within articles promotes clarity and cohesion.

Stability of articles

The Arbitration Committee has ruled that the Manual of Style is not binding, that editors should not change an article from one guideline-defined style to another without a substantial reason unrelated to mere choice of style, and that revert-warring over optional styles is unacceptable.1

Where there is disagreement over which style to use in an article, defer to the style used by the first major contributor.

Article titles, headings and sections

Article titles

This guidance applies to the titles of Wikipedia articles, not to the titles of external articles that are cited.

This guidance also applies to Section headings below.

Section headings

Shortcuts:
WP:HEAD
WP:MOSHEAD
WP:Headings
See also the guidance in "Article titles" immediately above, which applies to both article titles and section headings.

Section management

Shortcut:
MOS:SECTIONS

First sentences

First sentence content

The article should begin with a straightforward, declarative sentence that, as briefly as possible, provides the reader who knows nothing at all about the article's subject with the answer to two questions: "What (or who) is it?" and "Why is this subject notable?".2

First sentence format

As a general rule, the first (and only the first) appearance of the page title should be as early as possible in the first sentence and should be in boldface.7 However, if the title of a page is descriptive and does not appear verbatim in the main text, then it should not be in boldface.8

Capital letters

There are differences between the major varieties of English in the use of capitals (uppercase letters). Where this is an issue, the rules of the cultural and linguistic context apply. As for spelling, consistency is maintained within an article.

Within articles and other wiki pages, capitals are not used for emphasis. Where wording cannot provide the emphasis, italics are used.

Incorrect:    Contrary to popular belief, aardvarks are Not the same as anteaters.
Incorrect: Contrary to popular belief, aardvarks are NOT the same as anteaters.
Correct: Contrary to popular belief, aardvarks are not the same as anteaters.

Titles

Religions, deities, philosophies, doctrines and their adherents

Calendar items

Animals, plants and other organisms

Scientific names for genera and species are italicized, with a capital initial letter for the genus but no capital for the species; for more specific guidelines for article titles, see Wikipedia:WikiProject Tree of Life#Article titles. For example, the tulip tree is Liriodendron tulipifera, and humans are Homo sapiens. Taxonomic groups higher than genus are given with an initial capital and are not in italics; for example, gulls are in the family Laridae, and we are in the family Hominidae.

Common (vernacular) names of flora and fauna should be written in lower case—for example, oak or lion. There are a limited number of exceptions to this:

  1. Where the common name contains a proper noun, such as the name of a person or place, that proper noun should be capitalized (The Amur tiger may have a range of over 500 square kilometres; The Roosevelt elk is a subspecies of Cervus canadensis).
  2. For specific groups of organisms, there are specific rules of capitalization based on current and historic usage among those who study the organisms; for example, official common names of birds.
  3. In a very few cases, a set of officially established common names is recognized only within a country or a geographic region. Those common names may be capitalized according to local custom, but it should be understood that not all editors will have access to the references needed to support these names; in such cases, using the general recommendation is also acceptable.

A redirect from an alternative capitalization should be created where it is used in an article title.

In articles that cover two or more taxonomic groups, a consistent style of capitalisation should be used for species names. This could involve the use of:

Celestial bodies

Directions and regions

Institutions

Incorrect  (generic):    The University offers programs in arts and sciences.
Correct (generic): The university offers ...
Correct (title): The University of Delhi offers ...

Acronyms and abbreviations

Write out both the full version and the abbreviation at first occurrence
When introducing a new name in an article, it is good practice to use the full name on its first occurrence, followed by the abbreviated form in parentheses. For example, The New Democratic Party (NDP) won the 1990 Ontario election with a significant majority (first mention of New Democratic Party in the article), and The NDP quickly became unpopular with the voters (subsequent mention).
Initial capitals are not used in the full name of an item just because capitals are used in the abbreviation.
Incorrect  (not a name):    We used Digital Scanning (DS) technology
Correct:   We used digital scanning (DS) technology
Correct (name): produced by the British Broadcasting Corporation (BBC)
If the full term is already in parentheses, use a comma and or to indicate the abbreviation; for example, They first debated the issue in 1992 (at a convention of the New Democratic Party, or NDP).
Plural and possessive forms
Acronyms and initialisms are pluralized by adding -s or -es as with any other nouns (They produced three CD-ROMs in the first year; The laptops were produced with three different BIOSes in 2006). As with other nouns, no apostrophe is used unless the form is a possessive.
Periods (full stops) and spaces
Acronyms and initialisms are generally not separated by full stops (periods) or blank spaces (GNP, NORAD, OBE, GmbH); many periods and spaces that were traditionally required have now dropped out of usage (PhD is preferred over Ph.D. and Ph. D.). Periods are not used in units of measurement (see Wikipedia:Manual of Style (dates and numbers) for more information).
Truncated (Hon. for Honorable), compressed (cmte. for committee) and contracted (Dr. for Doctor) abbreviations may or may not be closed with a period; a consistent style should be maintained within an article. A period is more usual in American usage (Dr. Smith of 42 St. Joseph St.); no period is commonly preferred in British and other usage (Dr Smith of 42 St Joseph St, although one or other "St" might take a period, in such a case). Some British and other authorities prefer to drop the period from truncated and compressed abbreviations generally (XYZ Corp, ABC Ltd), a practice favored in science writing. Regardless of punctuation, such abbreviations are spaced if multi-word (op. cit. or op cit, not op.cit. or opcit).
US and U.S.
In American English, U.S. is the standard abbreviation for United States; US is becoming more common and is standard in other national forms of English. In longer abbreviations incorporating the country's initials (USN, USAF), periods are not used. When the United States is mentioned along with one or more other countries in the same sentence, U.S. or US can be too informal, and many editors avoid it especially at first mention of the country (France and the United States, not France and the U.S.). In a given article, if the abbreviated form of the United States appears predominantly alongside other abbreviated country names, for consistency it is preferable to avoid periods throughout; never add periods to the other abbreviations (the US, the UK and the PRC, not the U.S., the U.K. and the P.R.C.). The spaced U. S. is never used, nor is the archaic U.S. of A., except in quoted materials. U.S.A. and USA are not used unless quoted or as part of a proper name (Team USA).
Do not use unwarranted abbreviations
The use of abbreviations should be avoided when they would be confusing to the reader, interrupt the flow, or appear informal or lazy. For example, approx. for approximate or approximately should generally not be used, although it may be useful for reducing the width of an infobox or a table of data, or in a technical passage in which the term occurs many times.
See also Wikipedia:Manual of Style (dates and numbers) for when to abbreviate units of measurement.
Do not invent abbreviations or acronyms
Generally avoid the making up of new abbreviations, especially acronyms. For example, while it is reasonable to provide World Union of Billiards as a translation of Union Mondiale de Billard, the former is not the organization's name, and the organization does not use the acronym or initialism WUB; when referring to it in short form, use the official abbreviation UMB. In a wide table of international economic data, it might be desirable to abbreviate a United States gross national product heading; this might be done with the widely recognized initialisms US and GNP spaced together, with a link to appropriate articles, if it is not already explained: US GNP, rather than the made-up initialism USGNP.
HTML elements
The software that Wikipedia runs on does not support HTML abbreviation elements (<acronym> or <abbr>); therefore, these tags are not inserted into the source (see Mediazilla:671).

Italics

Further information: Wikipedia:Manual of Style (text formatting)
Emphasis
Italics are used sparingly to emphasize words in sentences (bolding is normally not used at all for this purpose). Generally, the more highlighting in an article, the less the effect of each instance.
Titles
Italics are used for the titles of works of literature and art, such as books, paintings and musical albums. The titles of articles, chapters, songs and other short works are not italicized, but are enclosed in double quotation marks.
Italics are not used for major revered religious works (for example the Bible, the Qur'an, and the Talmud).
Words as words
Italics are used when mentioning a word or letter (see Use–mention distinction) or a string of words up to a full sentence: "The term panning is derived from panorama, a word coined in 1787"; "The most commonly used letter in English is e". For a whole sentence, quotation marks may be used instead: (1) The preposition in She sat on the chair is on, or (2) The preposition in "She sat on the chair" is on. Mentioning (to discuss such features as grammar, wording and punctuation) is different from quoting (in which something is usually expressed on behalf of a quoted source).
Foreign words
Wikipedia prefers italics for phrases in other languages and for isolated foreign words that are not commonly used in everyday English.
Quotations in italics
For quotations, use only quotation marks (for short quotations) or block quoting (for long ones), not italics. (See Quotations below.) This means that (1) a quotation is not italicized inside quotation marks or a block quote just because it is a quotation, and (2) italicization is not used as a substitute for proper quotation formatting.
Italics within quotations
Italics are used within quotations if they are already in the source material, or are added by Wikipedia to give emphasis to some words. If the latter, an editorial note "[emphasis added]" should appear at the end of the quotation ("Now cracks a noble heart. Good night sweet prince: And flights of angels sing thee to thy rest" [emphasis added]).
If the source uses italics for emphasis, and it is desirable to stress that Wikipedia has not added the italics, the editorial note "[emphasis in original]" should appear after the quote.
Effect on nearby punctuation
Italicization is restricted to what should properly be affected by italics, and not the punctuation that is part of the surrounding sentence.
Incorrect:    What are we to make of that?
Correct: What are we to make of that?
      (The question mark applies to the whole sentence, not just to the emphasized that.)
Correct: Four of Patrick White's most famous novels are A Fringe of Leaves, The Aunt's Story, Voss and The Tree of Man.
(The commas, period, and and are not italicized.)
Italicized links
The italics markup must be outside the link markup, or the link will not work; however, internal italicization can be used in piped links.
Incorrect:    The opera [[''Turandot'']] is his best.
Correct: The opera ''[[Turandot]]'' is his best.
Correct: The [[USS Adder (SS-3)|USS ''Adder'' (SS-3)]] was a submarine.

Non-breaking spaces

See also: Wikipedia:Line break handling and Wikipedia:Manual of Style (dates and numbers)#Non-breaking spaces

Quotations

Shortcuts:
WP:MOSQUOTE
MOS:QUOTE
See also: Italics and quotations and Quotation marks
Minimal change
Wherever reasonable, preserve the original style, spelling and punctuation. Where there is a good reason not to do so, insert an editorial explanation of the changes, usually within square brackets (e.g., [for example]). If there is an error in the original statement, use sic, or {{sic}} (which produces sic), to show that it is not a transcription error.
Attribution
The author of a quote of a full sentence or more should be named; this is done in the main text and not in a footnote. However, attribution is unnecessary for quotations from the subject of the article or section. When preceding a quotation with its attribution, avoid characterizing it in a biased manner.
Quotations within quotations
When a quotation includes another quotation (and so on), start with double quotes outermost and working inward, alternate single-quotes with double quotes. For example, the following three-level quotation: "She disputed his statement that 'Voltaire never said "I disapprove of what you say, but I will defend to the death your right to say it."'" Adjacent quote marks, as at the end of this example, can be difficult to read (e.g.: "'") unless kerned apart slightly with CSS; the {{" '}}, {{' "}} and {{" ' "}} templates will accomplish this; the example above is output by ...your right to say it.{{" ' "}} in edit space. Extraneous normal or non-breaking space (&nbsp;) characters between the quotation marks should not be used; Wikipedia presents quotations, character for character, exactly as in the original.
Linking
Unless there is a good reason to do so, Wikipedia avoids linking from within quotes, which may clutter the quotation, violate the principle of leaving quotations unchanged, and mislead or confuse the reader.
Block quotations
A long quote (more than four lines, or consisting of more than one paragraph, regardless of number of lines) is formatted as a block quotation, which Wikimedia's software will indent from both margins. Block quotes are not enclosed in quotation marks (especially including decorative ones such as those provided by the {{cquote}} template, used only for pull quotes). Block quotes can be enclosed between a pair of <blockquote>...</blockquote> HTML tags, or {{quotation}} or {{quote}} can be used. Note: The current version of Wikipedia's MediaWiki software will not render multiple paragraphs inside a <blockquote> simply by spacing the paragraphs apart with blank lines. A workaround is to enclose each of the block-quoted paragraphs in its own <p>...</p> element.
Example:

<blockquote>
<p>And bring us a lot of [[horilka]], but not of that fancy kind with raisins, or with any other such things—bring us horilka of the purest kind, give us that demon drink that makes us merry, playful and wild!</p>

<p>—[[Nikolai Gogol]], ''[[Taras Bulba]]''</p>
</blockquote>

The result appears indented on both sides (and, depending on browser software, may also be in a smaller font):

And bring us a lot of horilka, but not of that fancy kind with raisins, or with any other such things—bring us horilka of the purest kind, give us that demon drink that makes us merry, playful and wild!

Nikolai Gogol, Taras Bulba

The {{quote}} template provides the same semantic HTML formatting, as well as a workaround for the paragraph spacing bug and a pre-formatted attribution line:

{{quote|And bring us a lot of horilka, but not of that fancy kind with raisins, or with any other such things—bring us horilka of the purest kind, give us that demon drink that makes us merry, playful and wild!|[[Nikolai Gogol]]|''[[Taras Bulba]]''}}

Which results in:

And bring us a lot of horilka, but not of that fancy kind with raisins, or with any other such things—bring us horilka of the purest kind, give us that demon drink that makes us merry, playful and wild!

Punctuation

Shortcuts:
WP:PUNC
WP:PUNCT

Apostrophes

Quotation marks

See also: Quotations

The term quotation(s) in the material below also includes other uses of quotation marks such as those for titles of songs, chapters, and episodes; unattributable aphorisms; literal strings; "scare-quoted" passages and constructed examples.

Double or single
Quotations are enclosed within "double quotes". Quotations within quotations are enclosed within 'single quotes'.
Inside or outside
Punctuation marks are placed inside the quotation marks only if the sense of the punctuation is part of the quotation. This system is referred to as logical quotation; it is used by Wikipedia both because of the principle of minimal change, and also because the method is less prone to misquotation, ambiguity and the introduction of errors in subsequent editing.
Correct: Arthur said "The situation is deplorable and unacceptable."
(The period is part of the quoted text.)
Correct: Arthur said that the situation was "deplorable".
(The period is not part of the quoted text.)
Correct: Martha asked, "Are you coming?"
(The question mark belongs inside because the quoted text itself was a question.)
Correct: Did Martha say, "Come with me"?
(The very quote is being questioned, so the question mark belongs outside; any punctuation at the end of the original quote is omitted.)
When quoting a sentence fragment that ends in a period, some judgment is required: if the fragment communicates a complete sentence, the period can be placed inside. The period should be omitted if the quotation is in the middle of a sentence.
Correct: Martha said, "Come with me", and they did.
If the sequence of juxtaposed punctuation marks seems distracting or untidy, try to obviate it.
Correct: Martha said, "Come with me" (and they did).
Article openings
When the title of an article appearing in the lead paragraph requires quotation marks (for example, the title of a song or poem), the quotation marks should not be in boldface, as they are not part of the title:
Correct: "Jabberwocky" is a nonsense poem by Lewis Carroll.
Block quotes
As already noted above, we use quotation marks or block quotes (not both) to distinguish long quotations from other text. Multiparagraph quotations are always block-quoted. The quotations must be precise and exactly as in the source. The source should be cited clearly and precisely to enable readers to find the text that supports the article content in question.
Quotation characters
The following types of quoting should not be used:
There are two options when considering the look of the quotation marks (that is, the glyph):
(Emphasis added to better distinguish between the glyphs.)
The exclusive use of straight quotes and apostrophes (see preceding section) is recommended. They are easier to type in reliably, and to edit. Mixed use interferes with searching (a search for Korsakoff's syndrome could fail to find Korsakoff’s syndrome and vice versa).
Whenever quotation marks or apostrophes appear in article titles, make a redirect from the same title but using the alternative glyphs.
Other matters

Brackets and parentheses

If a sentence contains a bracketed phrase, the sentence punctuation comes outside the brackets (as shown here). However, where one or more sentences are wholly inside brackets, their punctuation comes inside the brackets (see further details below). These rules apply to both round "( )" brackets, often called parentheses, and square "[ ]" brackets. There should not be a space next to a bracket on its inner side. An opening bracket should be preceded by a space, except in unusual cases; for example, when it is preceded by:

He rose to address the meeting: "(Ahem) ... Ladies and gentlemen, welcome!"
Only the royal characters in the play ([Prince] Hamlet and his family) habitually speak in blank verse.
We journeyed on the Inter[continental].

There should be a space after a closing bracket, except where another punctuation mark (other than an apostrophe or a dash) follows, and in unusual cases similar to those listed for opening brackets.

If sets of brackets must be nested, use the contrasting type (normally, square brackets appear within round brackets [like this]). Often, it is better to revise the sentence to reduce clutter, using commas, semicolons, colons or dashes instead.

Avoid adjacent sets of brackets—either put the parenthetic phrases in one set separated by commas, or rewrite the sentence. For example:

Incorrect:    Nikifor Grigoriev (c. 1885–1919) (also known as Matviy Hryhoriyiv) was a Ukrainian insurgent leader.
Correct: Nikifor Grigoriev (c. 1885–1919), also known as Matviy Hryhoriyiv, was a Ukrainian insurgent leader.
Correct: Nikifor Grigoriev (c. 1885–1919) was a Ukrainian insurgent leader. He was also known as Matviy Hryhoriyiv.

Square brackets are used to indicate editorial replacements and insertions of text. They serve three main purposes:

The use of square-bracketed wording should never alter the intended meaning of a quotation.

Sentences and brackets

Ellipses

Shortcuts:
WP:ELLIPSES
WP:ELLIPSIS

An ellipsis (plural ellipses) is an omission of material from quoted text or some other omission, perhaps of the end of a sentence, often used in the representation of conversation in print. The ellipsis is represented by ellipsis points, a series of three dots (or sometimes four at the end of a sentence).

Style
Ellipses have traditionally been implemented in three ways:
Function
Use an ellipsis if material is omitted in the course of a quotation, unless square brackets are used to gloss the quotation (see above, and the next point below). Put a space on each side of an ellipsis, except at the very start or end of a quotation. Sentence-final punctuation after an ellipsis is shown only if it is textually important (as is often the case with exclamation points and question marks, and rarely with periods); no space comes between the ellipsis and the terminal punctuation. Use non-breaking spaces (&nbsp;) only as needed to prevent improper line breaks, e.g.:
Pause or suspension of speech
Three periods are occasionally used to represent a pause in or suspense of speech, in which case the punctuation is retained in its original form (Virginia's startled reply was: "Could he...? No, I cannot believe it!"). This usage is avoided in Wikipedia except in direct quotations.
With square brackets
An ellipsis does not normally need square brackets around it, since its function is usually obvious—especially if the guidelines above are followed. Square brackets, however, may optionally be used for precision, to make it clear that the ellipsis is not itself quoted; this is usually only necessary if the quoted passage also uses three periods in it to indicate a pause or suspension. The ellipsis should follow exactly the principles given above, but with square brackets inserted immediately before and after it. (Her long rant continued: "How do I feel? How do you think I... look, this has gone far enough! [...] I want to go home!")

Commas

Shortcut:
WP:COMMA

Commas are the most frequently used marks in punctuation, but also the most difficult to use well. See the Comma article for general information about usage.

Serial commas

A serial comma (also known as the Oxford comma or Harvard comma) is a comma used immediately before a conjunction in a list of three or more items: the phrase ham, chips, and eggs contains a serial comma, while the variant ham, chips and eggs omits it. Both styles are acceptable in Wikipedia, but in a case where including or omitting the comma clarifies the meaning of the sentence, that solution should be adopted.

Sometimes omitting the comma can lead to an ambiguous sentence, as in this example: The author would like to thank her parents, Sinéad O'Connor and President Bush, which may be a list of either four people (the two parents and the two people named) or two people (O'Connor and Bush, who are the parents).

Including the comma can also cause ambiguity, as in: The author would like to thank her mother, Sinéad O'Connor, and President Bush, which may be a list of either two people (O'Connor, who is the mother, and Bush) or three people (the first being the mother, the second being O'Connor, and the third being Bush).

In such cases of ambiguity, there are three ways to clarify:

Colons

A colon (:) informs the reader that what comes after it proves, explains, or modifies what has come before, or is a list of items that have just been introduced. The items in such a list may be separated by commas; or, if they are more complex and perhaps themselves contain commas, the items should be separated by semicolons:

A colon may also be used to introduce direct speech enclosed within quotation marks (see above).

A colon should normally have a complete grammatical sentence before it:

Correct: He attempted it in two years: 1941 and 1943.
Incorrect:    The years he attempted it included: 1941 and 1943.
Correct (special case):    Spanish, Portuguese, French: these, with a few others, are the West Romance languages.

Sometimes (more in American than British usage) the word following a colon is capitalized, if that word effectively begins a new grammatical sentence, and especially if the colon serves to introduce more than one sentence:

No sentence should contain more than one colon.

Semicolons

A semicolon (;) is sometimes an alternative to a full stop, enabling related material to be kept in the same sentence; it marks a more decisive division in a sentence than a comma. If it separates clauses, they are usually independent; often only a comma or only a semicolon will be correct in a given sentence.

Correct: Though he had been here before, I did not recognize him.
Incorrect:    Though he had been here before; I did not recognize him.
Correct: Oranges are an acid fruit; bananas are classified as alkaline.
Incorrect:    Oranges are an acid fruit, bananas are classified as alkaline.

A semicolon does not force a capital letter in the word that follows it.

A sentence may contain several semicolons, especially when the clauses are parallel; multiple unrelated semicolons are often signs that the sentence should be divided.

Hyphens

Shortcut:
WP:HYPHEN

Hyphens (-) indicate conjunction. There are three main uses.

  1. To distinguish between homographs (re-dress = dress again, but redress = remedy or set right).
  2. To link certain prefixes with their main word (non-linear, sub-section, super-achiever):
    There is a clear trend, not yet complete, to join both elements in all varieties of English (subsection, nonlinear), particularly in North America. British English tends to hyphenate when the letters brought into contact are the same (non-negotiable, sub-basement) or are vowels (pre-industrial), or where a word is uncommon (co-proposed, re-target) or may be misread (sub-era, not subera). North American English reflects the same factors, but tends strongly to close up without a hyphen when possible. Consult a good dictionary, and see WP:ENGVAR.
  3. To link related terms in compound adjectives and adverbs:
Incorrect: 9-mm gap
Correct: 9 mm gap (entered as 9&nbsp;mm gap)
Incorrect:    9 millimetre gap
Correct: 9-millimetre gap
Correct: 12-hour shift
Correct: 12 h shift

Multi-hyphenated items: It is often possible to avoid multi-word hyphenated adjectives by rewording (a four-CD soundtrack album may be easier to read as a soundtrack album of four CDs). This is particularly important where converted units are involved (the 6-hectare-limit (14.8-acre-limit) rule might be possible as the rule imposing a limit of 6 hectares (14.8 acres), and the ungainly 4.9-mile (7.9 km) -long tributary as simply 4.9-mile (7.9 km) tributary).

Spacing: A hyphen is never followed or preceded by a space, except when hanging (see above) or when used to display parts of words independently, such as the prefix sub- and the suffix -less.

Minus signs: Do not use a hyphen (-) as a minus sign (−), except in code (see below).

Image filenames and redirects: A hyphen is used only to mark conjunction, not disjunction (for which en dashes are used: see below). An exception is in image filenames, where the ability to type the URL becomes more important (see the section on dashes below). Article titles with dashes should have a corresponding redirect from the title with hyphens: for example, Michelson-Morley experiment redirects to Michelson–Morley experiment, as the latter title, while correct, is harder to search for.

Hyphenation involves many subtleties that cannot be covered here; the rules and examples presented above illustrate the broad principles that inform current usage.

Dashes

Shortcuts:
MOS:DASH
WP:DASH

Two kinds of dashes are used on Wikipedia: en dashes and em dashes. The article on dashes shows common input methods for these.

Dashes should never be used in the filenames of images (use hyphens instead). If used in an article's title, there should be a redirect from the version with a hyphen.

En dashes

Shortcuts:
MOS:ENDASH
WP:ENDASH

En dashes (–) have three distinct roles.

  1. To indicate disjunction. In this role, there are two main applications.
  2. In lists, to separate distinct information within points—particularly track titles and durations, and musicians and their instruments, in articles on music albums. In this role, en dashes are always spaced.
  3. As a stylistic alternative to em dashes (see below).
En dashes in page names

When naming an article, a hyphen is not used as a substitute for an en dash that properly belongs in the title, for example in Eye–hand span. However, editors should provide a redirect page to such an article, using a hyphen in place of the en dash (e.g., Eye-hand span), to allow the name to be typed easily when searching Wikipedia. See also Wikipedia:Naming conventions (precision). The associated talk page name should match the page name exactly.

Minus signs

Do not use an en dash for negative signs and subtraction operators: use the correct Unicode character for the minus sign (&minus;) (see also Wikipedia:Manual of Style (mathematics).) Negative signs (−8 °C) are unspaced; subtraction signs (42 − 4 = 38) are spaced.

Em dashes

Em dashes (—) indicate interruption. They are used in two roles.

  1. Parenthesis (Wikipedia—one of the most popular web sites—has the information you need). Here, a pair of em dashes is a more arresting way of interpolating a phrase or clause than a pair of commas, and is less of an interruption than brackets. A pair of em dashes is particularly useful where there are already many commas; em dashes can make such a sentence easier to read, and sometimes they can remove ambiguity.
  2. A sharp break in the flow of a sentence—sharper than is provided by a colon or a semicolon.

Em dashes should not be spaced. Because em dashes are visually striking, it is preferable to avoid using more than two in a single paragraph. The roles of more than two em dashes in a single sentence can be unclear. Do not use an em dash for a minus sign.

Spaced en dashes as an alternative to em dashes

Spaced en dashes – such as here – can be used instead of unspaced em dashes in all of the ways discussed above. Spaced en dashes are used by several major publishers, to the complete exclusion of em dashes. One style should be used consistently in an article.

Other dashes

These are avoided on Wikipedia, notably the double-hyphen (--).

Slashes

Shortcut:
WP:SLASH

Avoid joining two words by a slash (/, also known as a forward slash), as it suggests that the two are related, but does not specify how. It is often also unclear how the construct would be read aloud. Consider replacing a slash with an explanation, or adding one in a footnote. Where possible, reword more fully to avoid uncertainties.

An example: The parent/instructor must be present at all times. Must both be present? (Then write the parent and the instructor.) Must at least one be present? (Then write the parent or the instructor.) Are they the same person? (Use a hyphen: the parent-instructor.)

In circumstances involving a distinction or disjunction, the en dash is usually preferable to the slash, e.g., the novel–novella distinction.

An unspaced slash may be used:

A spaced slash may be used:

Spaced slashes should be coded with a leading non-breaking space and a trailing normal space, e.g., x&nbsp;/ y (which renders as x / y), to prevent line breaks introducing readability problems.

The backslash character, \, is never used in place of a slash.

In general prose, prefer ÷ to / when representing mathematical division in the context of elementary arithmetic, as in "10 ÷ 2 = 5". In more advanced mathematical formulas, a vinculum or slash is preferred: \textstyle\frac{x^n}{n!} or \textstyle x^n/n!. (See Wikipedia:Manual of Style (dates and numbers)#Common mathematical symbols and Help:Displaying a formula for more information.)

And/or

The term and/or is usually awkward. In general, where it is important to mark an inclusive or, use x or y, or both, rather than x and/or y. For an exclusive or, use either x or y, and optionally add but not both, if it is necessary to stress the exclusivity.

Where more than two possibilities are presented, from which a combination is to be selected, it is even less desirable to use and/or. With two possibilities, at least the intention is clear; but with more than two it may not be. Instead of x, y, and/or z, use an appropriate alternative, such as one or more of x, y, and z; some or all of x, y, and z.

Sometimes or is ambiguous in another way: "Wild dogs, or dingoes, inhabit this stretch of land". Are wild dogs and dingoes the same or different? For one case write: "wild dogs (dingoes) inhabit ..." (meaning dingoes are wild dogs); for the other case write: "either wild dogs or dingoes inhabit ..."

Punctuation at the end of a sentence

Why me? she wondered.
The Homeric question is not Did Homer write the Iliad? but How did the Iliad come into being?, as we have now come to realise.
The door flew open with a BANG! that made them jump. [Not encyclopedic, but acceptable in transcription from audio, or of course in direct quotation.]