User:Eubulides/sandbox: Difference between revisions

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→‎Images: Suggest the Altviewer tool rather than a .js script; it'
→‎Images: Reflect WP:ALT more accurately, by saying when alt text can be omitted.
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* Editors are encouraged to add [[WP:ALT|alt text]] to all images for which it seems reasonable, including [[Help:Displaying a formula|math-mode equations]]. Alternative text describes the image for readers who cannot see the image, such as visually impaired readers or those using web-browsers that do not download images.
* Editors are encouraged to add [[WP:ALT|alt text]] to all images for which it seems reasonable, including [[Help:Displaying a formula|math-mode equations]]. Alternative text describes the image for readers who cannot see the image, such as visually impaired readers or those using web-browsers that do not download images.
**Instructions on adding alt text to equations and images can be found [[WP:ALT|here]]. The [[tools:~dispenser/cgi-bin/altviewer.py|Altviewer tool]] displays an article's alt text.
**Instructions on adding alt text to equations and images can be found [[WP:ALT|here]]. The [[tools:~dispenser/cgi-bin/altviewer.py|Altviewer tool]] displays an article's alt text.
** Alt text is not the same as [[WP:CAP|captions]]: alt text describes the image for those who cannot see it, whereas captions are intended to explain or supplement an image that is visible. Therefore, alt text should not be redundant with the caption or the main text of the article. [[WP:ALT|The guideline on this subject]] notes that images need not have alt text; editors should ask themselves how much sighted readers would lose if the picture were blanked, and how far that is describable in words. By default, no alt text is defined in images, provided that the <code>thumb</code> or <code>frame</code> parameter is included.
** Alt text is not the same as [[WP:CAP|captions]]: alt text describes the image for those who cannot see it, whereas captions are intended to explain or supplement an image that is visible. Therefore, alt text should not be redundant with the caption or the main text of the article. [[WP:ALT|The guideline on this subject]] notes that an image need not have alt text if it is purely decorative, that is, if it conveys no additional information and nothing happens when you click on it. Editors should ask themselves how much sighted readers would lose if the picture were blanked, and how far that is describable in words. By default, no alt text is defined in images, provided that the <code>thumb</code> or <code>frame</code> parameter is included.


=== Avoid entering textual information as images ===
=== Avoid entering textual information as images ===

Revision as of 21:08, 3 August 2009

The Manual of Style, often abbreviated MoS or MOS, is a style guide for Wikipedia articles. This main page contains basic principles. Additional subpages of the Manual of Style, listed and linked in the menu on the right-hand side of this page, explore some topics in more detail.

Pages in the Wikipedia project namespace—including the pages that make up the Manual of Style, other guidelines, and policies—can be searched by typing "WP:" followed by a search term in any Wikipedia search box. There is also an Editor's index to Wikipedia that includes MOS pages and other pages of interest to editors.

If the Manual of Style does not specify a preferred usage, discuss your issues on the Manual of Style talk page.

General principles

Internal consistency

An overriding principle is that style and formatting should be consistent within a Wikipedia article, though not necessarily throughout Wikipedia as a whole. One way of presenting information may be as good as another is, but consistency within an article promotes clarity and cohesion. Therefore, even where the Manual of Style permits alternative usages, be consistent within an article.

Stability of articles

The Arbitration Committee has ruled 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.

Follow the sources

Many points of usage, such as the treatment of proper names, can be decided by seeing what other writers do about the problem. Unless there is some clear reason to do otherwise, it is generally a good idea to follow the usage of reliable secondary sources in English on the subject; the sources for the article itself should be reliable. If the sources for the article can be shown to be unrepresentative of current English usage as a whole, follow current English usage instead—and consult more sources.

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.

  • Article titles should conform to Wikipedia's naming conventions, including "Use English".
  • Titles are generally nouns or noun phrases (Effects of the wild, not About the effects of the wild).
  • Titles should be short—preferably fewer than ten words.
  • The initial letter of a title is capitalized (except in very rare cases, such as eBay). Otherwise, capital letters are used only where they would be used in a normal sentence (Funding of UNESCO projects, not Funding of UNESCO Projects).
  • A, an, and the are normally avoided as the first word (Economy of the Second Empire, not The economy of the Second Empire), unless part of a proper noun (The Hague).
  • Special characters—such as the slash (/), plus sign (+), braces ({ }), and square brackets ([ ])—are avoided; the ampersand (&) is replaced by and, unless it is part of a formal name (Emerson, Lake & Palmer).

This guidance also applies to Section headings, below.

Section headings

See also the guidance in Article titles immediately above, which applies to both article titles and section headings.
  • Headings provide an overview in the table of contents and allow readers to navigate through the text more easily.
  • Change a heading only after careful consideration, because this will break section links to it within the same article and from other articles. If changing a heading, try to locate and fix broken links.
  • Section names should preferably be unique within a page; this applies even for the names of subsections. The disadvantages of duplication are that:
    • section names which are not unique produce nonstandard XHTML;[2]
    • after editing, the display can arrive at the wrong section; see also below; and
    • the automatic edit summary on editing a section with a non-unique name is ambiguous.
  • Section names should not normally contain links, especially ones that link only part of the heading; they will cause accessibility problems.
  • Section names should not explicitly refer to the subject of the article, or to higher-level headings, unless doing so is shorter or clearer. For example, Early life is preferable to His early life when His means the subject of the article; headings can be assumed to be about the subject unless otherwise indicated.
  • Capitalize the first letter of the first word and any proper nouns in headings, but leave the rest in lower case. Thus Rules and regulations, not Rules and Regulations.
  • Unspaced multiple equal signs are the style markup for headings. The triple apostrophes (''') that make words appear in boldface are not used in headings. The nesting hierarchy for headings is as follows:
    • the automatically generated top-level heading of a page is H1, which gives the article title;
    • primary headings are then ==H2==, followed by ===H3===, ====H4====, and so on.
  • Spaces between the == and the heading text are optional (==H2== versus == H2 ==). These extra spaces will not affect the appearance of the heading, except in the edit window.
  • A blank line below the heading is optional. If there are no blank lines above the heading, one line should be added, for readability in the edit window. Only two or more blank lines above or below will change the public appearance of the page by adding more white space.

Main article link

If a section is covered in a dedicated article, then this should be marked by inserting {{main|Article name}} directly beneath the section heading.

Section management

  • When linking to a section, as a courtesy, go to that article's section and leave an editor's note to remind others that the title is linked. List the names of the linking articles, so that if the title is altered, others can fix the links without having to perform exhaustive searches. For example:

==Evolutionary implications==<!--This section is linked from [[Richard Dawkins]] and [[Daniel Dennett]]-->

  • As well, consider a preemptive measure to minimize link corruption when the text of a heading changes by inserting an {{anchor}} with the old name with which to link to that heading section. For example:

==New section name{{anchor | Evolutionary implications}}==<!-- This section is linked from [[Richard Dawkins]] and [[Daniel Dennett]] -->

  • When referring to a section without linking, italicize the section name (italicize the actual section name only if it otherwise requires italics, such as the title of a book); for example, === Section management === but the current section is called Section management.
  • As explained in more detail at Wikipedia:Layout#Standard appendices and descriptions, optional appendix sections containing the following information may appear after the body of the article in the following order: (a) a list of books or other works created by the subject of the article, (b) a list of internal links to related Wikipedia articles, (c) notes and references, (d) a list of recommended relevant books, articles, or other publications that have not been used as sources, and (e) a list of recommended relevant websites that have not been used as sources.

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.

Capitals are not used for emphasis on Wikipedia. Where wording cannot provide the emphasis, use italics.

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.

Use of "The" mid-sentence

The definite article is not normally capitalized in the middle of a sentence; but there are idiomatic exceptions, including most titles of works of art, which should be quoted exactly. Common usage should be followed on a case-by-case basis. As usual, it is a good idea to consult the sources of the article.

Incorrect  (generic):    There was an article about The United Kingdom in The New York Times.
Correct (generic): There was an article about the United Kingdom in the New York Times.
Incorrect  (title):    J. R. R. Tolkien wrote the Lord of the Rings.
Correct (title): J. R. R. Tolkien wrote The Lord of the Rings.
Correct (title): Homer wrote the Odyssey.
Incorrect (exception): There are two seaside resorts in the Hague.
Correct (exception): There are two seaside resorts in The Hague.

Titles of people

  • When used generically, words such as president, king, and emperor are in lower case: De Gaulle was a French president and Louis XVI was a French king. Similarly: Three prime ministers attended the conference.
  • When used as parts of a title such words begin with a capital letter: President Obama, not president Obama. The formal name of an office is treated as a proper noun: The British Prime Minister is Gordon Brown, Hirohito was Emperor of Japan and Louis XVI was King of France (where Emperor of Japan and King of France are titles). Royal styles are capitalized: Her Majesty and His Highness; exceptions may apply for particular offices.

Religions, deities, philosophies, doctrines, and their adherents

  • Religions, sects, and churches and their followers (in noun or adjective form) start with a capital letter. Generally, the is not capitalized before such names (the Shī‘a, not The Shī‘a). (However, see also the style guide and naming convention for the Latter Day Saint movement.)
  • Religious texts (scriptures) are capitalized but often not italicized (for example, the names of the Bhagavad Gita, the Qur’an, the Talmud, the Granth Sahib, and the Bible). When the is used, it is not capitalized. Some derived adjectives are capitalized by convention, some are not (normally biblical but Koranic, for example); if unsure, check a dictionary appropriate to the topic, and be consistent within an article.
  • Honorifics for deities, including proper nouns and titles, start with a capital letter (God, Allah, the Lord, the Supreme Being, the Great Spirit, the Horned One, Bhagavan). The article "the" is not capitalized unless it is formally a part of the name of the deity. The same is true when referring to major religious figures and figures from mythology by titles or terms of respect (the Prophet, the Messiah, the Virgin). Common nouns denoting deities or religious figures are not capitalized; thus the Romans worshipped many gods, many Anglo-Saxons worshipped the god Wotan, Jesus and Muhammad are both considered prophets in Islam, biblical scholars dispute whether Mary was a virgin for her entire life, and her husband was her muse (but the nine Muses).
  • Pronouns and possessives referring to figures of veneration are not capitalized in Wikipedia articles, even when they traditionally are in a religion's scriptures. They are left capitalized when directly quoting scriptures or any other texts that capitalize them.
  • Broad categories of mythical or legendary creatures do not start with uppercase capital letters (elf, fairy, nymph, unicorn, angel), although in derived works of fantasy, such as the novels of J.R.R. Tolkien and real-time strategy video games, initial capitals are sometimes used to indicate that the beings are regarded as cultures or races in their fictional universes. Names or titles of individual creatures are capitalized (the Minotaur, the Pegasus) as are those of groups whose name and membership are fixed (the Cherubim, the Magi or the Three Wise Men). As with terms for deities, generalized references are not capitalized (cherub-like, the priests of this sect were called magi by some, several wise men were consulted).
  • Spiritual or religious events are likewise capitalized only when they are terms referring to specific incidents or periods (the Great Flood, the Exodus, but annual flooding and an exodus of refugees).
  • Philosophies, theories, and doctrines do not begin with a capital letter unless the name derives from a proper noun (capitalism versus Marxism) or has become a proper noun (lowercase republican refers to a system of political thought; uppercase Republican refers to one of several specific political parties or ideologies, such as the US Republican Party or Irish Republicanism). Doctrinal topics or canonical religious ideas (as distinguished from specific events) capitalized by some religious adherents are given in lower case in Wikipedia, such as virgin birth, original sin, or transubstantiation.
  • Platonic or transcendent ideals are capitalized (Good, Truth), but only within the context of philosophical doctrine; used more broadly, they are in lower case (Superman represents American ideals of truth and justice). Personifications represented in art, such as a statue of the figure Justice, are capitalized.

Calendar items

  • Months, days of the week, and holidays start with a capital letter: June, Monday, the Fourth of July (when referring to the U.S. Independence Day, otherwise July 4 or 4 July).
  • Seasons, in almost all instances, are lowercase: This summer was very hot; The winter solstice occurs about December 22; I have spring fever. When personified, season names may function as proper nouns, and they should then be capitalized: I think Spring is showing her colors; Old Man Winter.

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 particular groups of organisms, there are particular 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 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 capitalization should be used for species names. This could involve the use of:

  • scientific names throughout (often appropriate for specialist articles);
  • title case for common names of species throughout (see WP:BIRDS) and lower case for non-specific names such as eagle or bilberry, which may work well for articles with a broad coverage of natural history; or
  • lower-case initial letters for common names, which may work well for non-specialist articles that happen to refer to different taxonomic groups.

Celestial bodies

  • When used generally, the words sun, earth, and moon do not take capitals: The sun was peeking over the mountain top and The greatest cobalt deposit on earth. The sun, earth, and moon take capitals when personified: Sol Invictus ("Unconquered Sun") was the Roman sun god. They are also capitalized when used in a sentence mentioning astronomical bodies that take capitals: The Moon orbits the Earth, but Io is a moon of Jupiter.
  • Names of planets, moons, asteroids, comets, stars, constellations, and galaxies are proper nouns and start with a capital letter: The planet Mars can be seen tonight in the constellation Gemini, near the star Pollux. and Halley's Comet is the most famous of the periodic comets. and The Andromeda Galaxy is a spiral galaxy. When a name has more than one word, it is treated like other proper nouns with each first letter capitalized: Alpha Centauri and not Alpha centauri; Milky Way and not Milky way.

Directions and regions

  • Directions such as north are not proper nouns and do not take capitals. The same is true for their related forms: someone might call a road that leads north a northern road, compared with the Great North Road. Composite directions may or may not be hyphenated, depending on the general style adopted in the article (Southeast Asia and northwest in American English, but South-East Asia and north-west in British English).
  • Regions that are proper nouns, including widely known expressions such as Southern California, start with a capital letter. Similarly, a person from the Southern United States is a Southerner. If uncertain whether to capitalize, do not.

Institutions

  • Names of institutions (the University of Sydney, George Brown College) are proper nouns and require capitals. The at the start of a title is not normally capitalized (a degree from the University of Sydney).
  • Generic words for institutions (university, college, hospital, high school) do not need capitals:
Incorrect  (generic):    The University offers programs in arts and sciences.
Correct (generic): The university offers ...
Correct (title): The University of Delhi offers ...
  • Bodies of government, such as cities, towns and countries, follow the same rules: the names of specific cities, towns, countries, etc., are proper nouns and require capitals but generic words for types of government bodies do not take capitals. Sometimes, the full official name of a body is not needed.
Incorrect  (generic):    The City has a population of 55,967.
Correct (generic): The city has ...
Correct (title): The City of Smithville has ...
Correct (skip type): Smithville has ...

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, like other nouns, become pluralis by adding -s or -es (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). Periods and spaces that were traditionally required have now dropped out of usage (PhD is now preferred over Ph.D. and Ph. D.). Full stops (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 full stop 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). British and some other authorities prefer to drop the stop 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. (with periods) is the standard abbreviation for United States; US (without periods) is the standard abbreviation in other national forms of English and is becoming increasingly common in American English. In longer abbreviations incorporating the country's initials (USN, USAF), periods are not used. When the United States is mentioned 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 full stops 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
Avoid abbreviations 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

Emphasis
Italics are used sparingly to emphasize words in sentences (and boldface 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, films (feature-length), television series, and musical albums. The titles of articles, chapters, songs, television episodes, short films, 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?
      (Note the difference between ? and ?. 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

Template:Mergesection

  • A non-breaking space (also known as a hard space) is recommended to prevent the end-of-line displacement of elements that could be awkward at the beginning of a new line:
    • in many compound expressions in which figures and abbreviations or symbols are separated by a space (17 kg, AD 565, 2:50 pm), including scientific names of species where the genus is abbreviated (C. elegans);
    • in other places where displacement might be disruptive to the reader, such as £11 billion, 5° 24′ 21.12″ N, Boeing 747, and the first two items in 7 World Trade Center.
  • A hard space can be produced with the HTML code &nbsp; instead of the space bar: 19&nbsp;kg yields a non-breaking 19 kg.
  • Hard spaces can also be produced by using the {{nowrap}} template: {{nowrap|8 sq ft}} produces a non-breaking 8 sq ft. This is especially useful for short constructions requiring two or more hard spaces, as in the preceding example. Template {{nowrap}} has the disadvantage that if the enclosed text starts or ends with a space, these spaces are forced outside in the resulting HTML, and unpredicted breaks may occur. If &nbsp; occurs right before {{nowrap}}, or at the start of text within {{nowrap}}, some browsers allow a break at that point.
  • Unlike normal spaces, multiple hard spaces are not compressed by browsers into a single space.

Quotations

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 the error was not made in transcription.
Use ellipses to indicate omissions from quoted text. Legitimate reasons for omitting parts of quotation include removing extraneous, irrelevant, or parenthetical words and skipping unintelligible or guttural speech (umm, ahh, and hmm, for example). Do not selectively quote or omit text where doing so would alter the meaning of the quoted text or would omit essential context.
Allowable typographical changes
Although the requirement of minimal change is strict, a few purely typographical elements of quoted text should be conformed to English Wikipedia's typographical conventions without comment. This practice of conforming typographical styling to a publication's own "house style" is universal. Allowable typographical alterations include these:
  • Styling of dashes—use the style chosen for the article: unspaced em-dash or spaced en-dash. See Dashes below.
  • Styling of apostrophes and quotation marks: they should all be straight, not curly. See Quotation marks below. In quoting foreign-language text, replace foreign typographical elements such as guillemets (« ») with their English-language equivalents. Replace guillemets with straight quotation marks, for example.
  • Remove spaces before periods, colons, semicolons, and the like. This spacing is alien to English Wikipedia's conventions and to modern English-language publishing.
  • Some text styling (of course the typeface will be automatically made the same as the article's default typeface; but preserve bold, underlining, and italics; see Italics, above).
Quotations within quotations
When a quotation includes another quotation (and so on), start with double quote marks outermost, and, working inward, alternate single with double quote marks. The following example has three levels of 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.
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.
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. For example writing:

<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>

will result in the following, indented on both sides (it may also be in a smaller font, depending on browser software):

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

Apostrophes

  • Consistent use of the straight (or typewriter) apostrophe ( ' ) is recommended, as opposed to the curly (or typographic) apostrophe (  ). For details and reasons, see Quotation marks, below.
  • For the possessive apostrophe, see the summary of usage issues at Possessives, below.
  • Foreign characters that resemble apostrophes, such as transliterated Arabic ayin ( ʿ ) and alif ( ʾ ), are represented by their correct Unicode characters, despite possible display problems. If this is not feasible, use a straight apostrophe instead.
  • For a thorough treatment of all uses of the apostrophe (possessive, elision, formation of certain plurals, specific foreign-language issues) see the article Apostrophe.

Quotation marks

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

Double or single
Quotations are enclosed within double quotes (e.g., Bob said: "Jim ate the apple."). Quotations within quotations are enclosed within single quotes (e.g., Bob said: "Did Jim say 'I ate the apple' after he left?"). Search engines may not find quotations within single quotes, like 'I ate the apple'
Inside or outside

Template:Disputedguidelinetag

On Wikipedia, place all punctuation marks inside the quotation marks if they are part of the quoted material and outside if they are not. This practice 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:
  • Grave and acute accents or backticks (`text´) are neither quotation marks nor apostrophes, and must not be used in their place.
There have traditionally been two styles concerning the look of the quotation marks (that is, the glyph):
  • Typewriter or straight style: "text", 'text'. Recommended.
  • Typographic or curly style: text, text. Not recommended.
(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 some searches, such as those using the browser's search facility (a search for Alzheimer's disease could fail to find Alzheimer’s disease 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
  • A quotation is not italicized simply because it is a quotation.
  • If an entire sentence is quoted in such a way that it becomes a grammatical part of the larger sentence, the first letter loses its capitalization: It turned out to be true that "a penny saved is a penny earned".
  • If a word or phrase appears in an article in single quotes, such as 'abcd', Wikipedia's search facility will find that word or phrase only if the search string is also within single quotes. This difficulty does not arise for double quotes, and this is one of the reasons the latter are recommended.

Brackets and parentheses

These rules apply to both round brackets ( ( ) ), often called parentheses, and square brackets ( [ ] ).

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 Sentences and brackets below). There should be no space next to a bracket's inner side. An opening bracket should be preceded by a space, except in unusual cases; for example, when it is preceded by:

  • An opening quotation mark:

    He rose to address the meeting: "(Ahem) ... Ladies and gentlemen, welcome!"

  • Another opening bracket:

    Only the royal characters in the play ([Prince] Hamlet and his family) habitually speak in blank verse.

  • A portion of a word:

    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 are nested, use different types for adjacent levels of nesting; for two levels, it is customary to have square brackets appear within round brackets. This is often a sign of excessively convoluted expression; it is often better to recast, linking the thoughts with commas, semicolons, colons, or dashes.

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 within quotations. They serve three main purposes:

  • To clarify. ("She attended [secondary] school"—where this was the intended meaning, but the type of school was unstated in the original sentence.)
  • To reduce the size of a quotation. If a source says, "X contains Y, and under certain circumstances, X may contain Z as well", it is acceptable to reduce this to "X contains Y [and sometimes Z]", without ellipsis. When an ellipsis (...; see below) is used to indicate material removed from a direct quotation, it should not normally be bracketed.
  • To make the grammar work: She said that "[she] would not allow this" – where her original statement was "I would not allow this". (Generally, though, it is better to begin the quotation after the problematic word: She said that she "would not allow this.")

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

Sentences and brackets

  • If any sentence includes material that is enclosed in square or round brackets, it still must end—with a period, or a question or exclamation mark—after those brackets (a rule that applies in all English, whether British or U.S.). The preceding sentence is an example. This principle applies no matter what punctuation is used within the brackets.
  • However, if the entire sentence is within brackets, the closing punctuation falls within the brackets. (This sentence is an example.) This does not apply to matter that is added (or modified editorially) at the beginning of a sentence for clarity, which is usually in square brackets: "[Principal Skinner] already told me that", he objected in preference to the potentially more ambiguous "He already told me that", he objected, but even here consider "He [Principal Skinner] already told me that", he objected.
  • A sentence that occurs within brackets in the course of another sentence does not generally have its first word capitalized just because it starts a sentence. The enclosed sentence may have a question mark or exclamation mark added, but not a period: Alexander then conquered (who would have believed it?) most of the known world; Clare demanded that he drive (she knew he hated driving) to the supermarket. It is often clearer to separate the thoughts into separate sentences or clauses: Alexander then conquered most of the known world. Who would have believed it? or Clare demanded that he drive to the supermarket; she knew he hated driving.

Ellipses

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 a printed record of conversation. The ellipsis is represented by ellipsis points: a set of three dots.

Style
Ellipsis points, or ellipses, have traditionally been implemented in three ways:
  • Three unspaced periods (...). This is the easiest way, and gives a predictable appearance in HTML. Recommended.
  • Pre-composed ellipsis character (); generated with the &hellip; character entity, or as a literal "…". This is harder to input and edit, and too small in some fonts. Not recommended.
  • Three spaced periods (. . .). This is an older style that is unnecessarily wide and requires non-breaking spaces to keep it from breaking at the end of a line. Not recommended.
Function and implementation
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 points below).
  • Put a space on each side of an ellipsis, except that there should be no space between an ellipsis and:
    • a quotation mark, where the ellipsis is on the inside
    • a parenthesis or a bracket, where the ellipsis is on the inside
    • sentence-final punctuation, or a colon, semicolon, or comma (all rare), following the ellipsis
  • 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).
  • Use non-breaking spaces (&nbsp;) only as needed to prevent improper line breaks, e.g.:
    • To keep a quotation mark from being separated from the start of the quotation: "...&nbsp;we are still worried."
    • To keep the ellipsis from wrapping to the next line: "France, Germany,&nbsp;... and Belgium but not the USSR."
Pause or suspension of speech
Three periods (loosely also called ellipsis points) 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 at 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

Commas are the most frequently used marks in punctuation, but also the most difficult to use well. Some important points are made at Semicolons, below. Other points include these:

  • A pair of commas is often used for parenthetic material, and it interrupts the sentence less than parentheses (brackets) or dashes. Sometimes other punctuation can mask the need for a comma, especially the second in such a pair when parentheses are also used.
Incorrect: Burke and Wills, fed by local Aborigines (on beans, fish, and "ngardu") survived for a few months.
Correct:    Burke and Wills, fed by local Aborigines (on beans, fish, and "ngardu"), survived for a few months.
  • A comma is very rarely correct immediately before an opening parenthesis.
  • Modern practice is against excessive use of commas; there are usually ways to simplify a sentence so that fewer are needed.
Awkward: Mozart was, along with the Haydns, both Joseph and Michael, and also Beethoven, one of Schubert's heroes.
Much better:    Schubert's heroes included Mozart, Beethoven, and Joseph and Michael Haydn.

Serial commas

A serial comma (also known as an Oxford comma or a 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, with consistency in an article; 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 thanked her parents, Sinéad O'Connor and Prime Minister Blair, which may list either four people (the two parents and the two people named) or two people (O'Connor and Blair, who are the parents).

Including the comma can also cause ambiguity, as in: The author thanked her mother, Sinéad O'Connor, and Prime Minister Blair, which may list either two people (O'Connor, who is the mother, and Blair) or three people (the first being the mother, the second O'Connor, and the third Blair).

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

  • Use or omit the serial comma to avoid ambiguity.
  • Recast the sentence.
  • Format the list, perhaps with paragraph breaks and numbered paragraphs.

Recasting example one:

  • To list four people: The author thanked Prime Minister Blair, Sinéad O'Connor, and her parents.
  • To list two people (the commas here set off non-restrictive appositives): The author thanked her father, Prime Minister Blair, and her mother, Sinéad O'Connor.

Recasting example two:

  • To list two people: The author thanked Prime Minister Blair and her mother, Sinéad O'Connor.
  • To list three people: The author thanked her mother, Prime Minister Blair, and Sinéad O'Connor

Note that the last example's being clear depends on the reader knowing that P.M. Blair is male and cannot be a mother. If we change the example slightly, we are back to an ambiguous statement: The author thanked her mother, Irish President Mary McAleese, and Sinéad O'Connor.

Recasting again:

  • To list three people: The author thanked President Mary McAleese, Sinéad O'Connor, and her mother.

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:

We visited several tourist attractions: the Leaning Tower of Pisa, which I thought could fall at any moment; the Bridge of Sighs; the supposed birthplace of Petrarch, or at least the first known house in which he lived; and so many more.

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, except sometimes when it introduces items set off in new lines like the very next colon here. Examples:

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:

The argument is easily stated: We have been given only three tickets. There are four of us here: you, the twins, and me. The twins are inseparable. Therefore, you or I will have to stay home.

No sentence should contain more than one colon, and a colon should never be followed by a hyphen or dash.

Semicolons

A semicolon (;) is sometimes an alternative to a full stop (period), 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.

In very rare cases, a comma may be used where a semicolon would seem to be called for:

Accepted: "Life is short, art is long." (citing a brief aphorism; see Ars longa, vita brevis)
Accepted: "I have studied it, you have not." (reporting brisk conversation, like this reply of Newton's)

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 into shorter sentences, or otherwise refashioned.

Unwieldy: Oranges are an acid fruit; bananas are classified as alkaline; pears are close to neutral; these distinctions are rarely discussed.
One better way:    Oranges are an acid fruit, bananas are alkaline, and pears are close to neutral; these distinctions are rarely discussed.

Hyphens

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

  1. To distinguish between homographs (re-dress means dress again, but redress means remedy or set right).
  2. To link certain prefixes with their main word (non-linear, sub-section, super-achiever).
    • There is a clear trend to join both elements in all varieties of English (subsection, nonlinear), particularly in American English. 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). American English reflects the same factors, but tends 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:
    • A hyphen can help with ease of reading (face-to-face discussion, hard-boiled egg); a hyphen is particularly useful in long nominal groups where non-experts are part of the readership, such as in Wikipedia's scientific articles: gas-phase reaction dynamics.
    • A hyphen can help to disambiguate (little-celebrated paintings, not a reference to little paintings).
    • Many compound adjectives that are hyphenated when used attributively (before the noun they qualify—a light-blue handbag), are not hyphenated when used predicatively (after the noun—the handbag was light blue); this attributive hyphenation also occurs in proper names, such as Great Black-backed Gull. Where there would be a loss of clarity, the hyphen may be used in the predicative case too (hand-fed turkeys, the turkeys were hand-fed).
    • A hyphen is not used after a standard -ly adverb (a newly available home, a wholly owned subsidiary) unless part of a larger compound (a slowly-but-surely strategy). Some words ending in -ly function as both adverbs and adjectives (a friendly-looking driver, the natives used us friendly and with kindness). Some such dual-purpose words (like early, only, northerly) are not standard -ly adverbs, since they are not formed by addition of -ly to an independent current-English adjective. These need careful treatment: Early flowering plants evolved along with sexual reproduction, but Early-flowering plants risk damage from winter frosts; northerly-situated islands.
    • A hyphen is normally used when the adverb well precedes a participle used attributively (a well-meaning gesture; but normally a very well managed firm, since well itself is modified); and even predicatively, if well is necessary to, or alters, the sense of the adjective rather than simply intensifying it (the gesture was well-meaning, the child was well-behaved, but the floor was well polished).
    • A hanging hyphen is used when two compound adjectives are separated (two- and three-digit numbers, a ten-car or -truck convoy, sloping right- or leftward, but better is sloping rightward or leftward).
    • Values and units used as compound adjectives are hyphenated only where the unit is given as a whole word. Where hyphens are not used, values and units are always separated by a non-breaking space (&nbsp;).
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

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

En dashes () have three distinct roles.

  1. To indicate disjunction. In this role, there are two main applications.
    • To convey the sense of to or through, particularly in ranges (pp. 211–19, 64–75%, the 1939–45 war, May–November) and where movement is involved (Dublin–Belfast route). The word to, rather than an en dash, is used when a number range involves a negative value or might be misconstrued as a subtraction (−3 to 1, not −3–1). This is also the case when the nearby wording demands it, e.g., he served from 1939 to 1941 and not he served from 1939–1941, in which from and to are complementary and should both be spelled out.
    • As a substitute for some uses of and, to, or versus for marking a relationship involving independent elements in certain compound expressions (Canada–US border, blood–brain barrier, time–altitude graph, 4–3 win in the opening game, male–female ratio, 3–2 majority verdict, Lincoln–Douglas debate, diode–transistor logic; but a hyphen is used in Sino-Japanese trade, in which Sino-, being a prefix, lacks lexical independence.)
      • Spacing: All disjunctive en dashes are unspaced, except when there is a space within either one or both of the items (the New York – Sydney flight; the New Zealand – South Africa grand final; June 3, 1888 – August 18, 1940, but June–August 1940).
  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 names of a page and its associated talk page should match 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 operators (42 − 4 = 38) are spaced.

Em dashes

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

  1. Parenthetical (Wikipedia—one of the most popular web sites—has the information you need). A pair of em dashes for such interpolations is more arresting than a pair of commas, and less disruptive than parentheses (round brackets).
  2. As a sharp break in the flow of a sentence—sharper than is provided by a colon or a semicolon.
  • In both roles, em dashes are useful where there are already several commas; em dashes can clarify the structure, sometimes removing ambiguity.
  • Use em dashes sparingly. They are visually striking, so two in a paragraph is often a good limit. Avoid two "sharp break" em dashes in a sentence, since they are readily mistaken for a parenthetic pair. Do not use more than two em dashes in a single sentence: which two (if any) make a parenthetic pair?
  • Em dashes should not be spaced.
  • 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 in two consecutive hyphens. (--).

Slashes

Avoid joining two words by a slash, also known as a forward slash ( / ). It suggests that the two are related, but does not specify how. It is often also unclear how the construct would be read aloud. Replace with clearer wording.

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 (see above) is usually preferable to the slash, e.g., the novel–novella distinction.

An unspaced slash may be used:

  • to indicate phonemic pronunciations (ribald is pronounced /ˈrɪbəld/)
  • to separate the numerator and denominator in a fraction (7/8 or 78)
  • to indicate regular defined yearly periods that do not coincide with calendar years (see Wikipedia:Manual of Style (dates and numbers)#Longer periods)
  • where a slash occurs in a phrase widely used outside Wikipedia, and a different construction would be inaccurate, unfamiliar, or ambiguous

A spaced slash may be used:

  • to separate run-in lines when quoting poetry or song (To be or not to be: that is the question: / Whether 'tis nobler in the mind to suffer / The slings and arrows of outrageous fortune), or rarely when quoting prose, where careful marking of a paragraph break is textually important
  • to separate items that include at least one internal space (the NY 31 east / NY 370 exit), where for some reason use of a slash is unavoidable

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 improper line breaks.

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

Prefer the division operator ( ÷ ) to ( / ) when representing elementary arithmetic in general prose: 10 ÷ 2 = 5. In more advanced mathematical formulas, a vinculum or slash is preferred: or . (See Wikipedia:Manual of Style (dates and numbers)#Common mathematical symbols and Help:Displaying a formula.)

And/or

The term and/or is awkward (see and/or). In general, where it is important to mark an inclusive or (see inclusive or), use x or y, or both, rather than x and/or y. For an exclusive or (see 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

  • Periods (referred to as full stops by most non-US English speakers), question marks, and exclamation marks are the three sentence-enders: the only punctuation marks used to end sentences.
  • In some contexts, no sentence-ender should be used; in such cases, the sentence often does not start with a capital letter. See Quotations, Quotation marks and Sentences and brackets, above.
  • For the use of three periods in succession, see Ellipses, above.
  • Clusters of question marks, exclamation marks, or a combination of them (such as the interrobang) are highly informal, and inappropriate in Wikipedia articles.
  • The exclamation mark is used with restraint: it is an expression of surprise or emotion that is generally unsuited to a scholarly or encyclopedic register.
  • Question marks and exclamation marks may sometimes be used in the middle 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 realize.
  • 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.]
  • Along with commas, semicolons, and colons, sentence-enders are never preceded by a space in normal prose.
  • There is no guideline on whether to use one space or two after the end of a sentence (see Double-spaced sentences), but the issue is not important, because the difference is visible only in edit boxes; that is, it is ignored by browsers when displaying the article.

Punctuation and inline citations

Inline citations are generally placed after any punctuation such as a comma or period, with no intervening space:

... are venomous.<ref>See OED, "viper, n."</ref>

(yielding ... are venomous.(refactored from ref) and later, (refactored from ref) See OED, "viper, n.")

See Wikipedia:Citing sources for general guidelines about referencing.

Punctuation after formulae

A sentence that ends with a formula should have a sentence-ender (period, exclamation mark, or question mark) after the formula. Within a sentence, other punctuation (such as comma or colon) is used after a formula just as it would be if the text were not a formula. See Wikipedia:Manual of Style (mathematics)#Punctuation after formulas.

Geographical items

Places should generally be referred to consistently using the same name as in the title of their article (see the geographic naming conventions). Exceptions are made if there is a widely accepted historical English name approriate to the given context. In cases where such a historical name is used, it should be followed by the modern name in parentheses on the first occurrence of the name in applicable sections of the article. This resembles linking; it should not be done to the detriment of style. On the other hand, it is probably better to do it too often than too rarely. If more than one historic name is applicable for a given historical context, the other names should be added after the modern English name, that is: "historical name (modern name, other historical names)".

Chronological items

Precise language

Avoid statements that will age quickly, except on pages concerning current events which are frequently brought up to date. Avoid recently, soon, and now (unless their meaning is fixed by the context). Avoid relative terms like currently (usually redundant), in modern times, is now considered, and is soon to be superseded. Instead, use either:

  • more precise and absolute expressions (since the start of 2005; during the 1990s; is expected to be superseded by 2008); or
  • an as of phrase (as of August 2007), which signals the time-dependence of the statement, and alerts later editors to update the statement (see As of); or simply use at instead: The population was over 21,000,000 (at December 2008).

Times

Context determines whether the 12-hour clock or 24-hour clock is used; in both, colons separate hours, minutes, and seconds (1:38:09 pm and 13:38:09).

  • 12-hour clock times end with dotted or undotted lower-case a.m. or p.m., or am or pm, which are spaced (2:30 p.m. or 2:30 pm, not 2:30p.m. or 2:30pm). A hard space (see above) is advisable: 2:30&nbsp;pm. Noon and midnight are used rather than 12 pm and 12 am; whether midnight refers to the start or the end of a date will need to be specified unless this is clear from the context.
  • 24-hour clock times have no a.m., p.m., noon or midnight suffix. Discretion may be used as to whether the hour has a leading zero (08:15 or 8:15). 00:00 refers to midnight at the start of a date, 12:00 to noon, and 24:00 to midnight at the end of a date.

Dates

  • Wikipedia does not use ordinal suffixes or articles, or put a comma between month and year.
Incorrect:    February 14th, 14th February, the 14th of February
Correct: 14 February, February 14
Incorrect: October, 1976; October of 1976
Correct: October 1976
  • For guidance on which of the two standard formats to use (day before month or month before day), see WP:MOSNUM#Full date formatting.
  • Dates are not normally linked.[3]
  • Date ranges are preferably given with minimal repetition, using an unspaced en dash where the range involves numerals alone (5–7 January 1979; January 5–7, 2002) or a spaced en dash where opening and/or closing dates have internal spaces (5 January – 18 February 1979; January 5 – February 18, 1979).
  • Rarely, a night may be expressed in terms of the two contiguous dates using a slash (the bombing raids of the night of 30/31 May 1942).
  • Yearless dates (5 March, March 5) are inappropriate unless the year is obvious from the context. There is no such ambiguity with recurring events, such as January 1 is New Year's Day.
  • ISO 8601 dates (like 1976-05-13) are uncommon in English prose and are generally not used in Wikipedia. However, they may be useful in long lists and tables for conciseness and ease of comparison. Years outside the range 1583 through 9999, or dates in any calendar except the Gregorian calendar, do not comply with the ISO 8601 standard.[4]

Longer periods

  • Write Months as whole words (February, not 2), except in the ISO 8601 format. Use abbreviations such as Feb only where space is extremely limited, such as in tables and infoboxes. Do not insert of between a month and a year (April 2000, not April of 2000).
  • Seasons as dates. As the seasons are reversed in the northern and southern hemispheres—and areas near the equator tend to have just wet and dry seasons—neutral wording (in early 1990, in the second quarter of 2003, around September) may be preferable to a "seasonal" reference (Summer 1918, Spring 1995). Even when the season reference is unambiguous (for instance when a particular location is clearly involved) a date or month may be preferable to a season name, unless there is a logical connection (the autumn harvest). Season names are actually preferable when they refer to a time of the year rather than as a substitute for a date or range of dates (migration to higher latitudes typically starts in mid spring). Season names in this kind of context are spelled with a lower-case initial.
  • Years
    • Years are normally expressed in digits; a comma is not used in four-digit years (1988, not 1,988).
    • Avoid inserting the words the year before the digits (1995, not the year 1995), unless the meaning would otherwise be unclear.
    • Years are numbered according to the western calendar eras based on the traditionally reckoned year of the conception or birth of Jesus.
      • AD and BC are the traditional ways of referring to these eras. However, the CE and BCE is becoming more common in academic and some religious writing. No preference is given to either style.
        • Do not use CE or AD unless the date would be ambiguous without it. e.g. "The Norman Conquest took place in 1066." not 1066 CE or AD 1066.
        • BCE and CE or BC and AD are written, in upper case, spaced, and without periods (full stops).
        • Use either the BC-AD or the BCE-CE notation, but not both in the same article. AD may appear before or after a year (AD 106, 106 AD); the other abbreviations appear after (106 CE, 3700 BCE, 3700 BC).
        • Do not change from one style to another unless there is substantial reason for the change, and consensus for the change with other editors.
      • Uncalibrated (bce) radiocarbon dates: Do not give uncalibrated radiocarbon dates (represented by the lower-case bce unit, occasionally bc or b.c. in some sources), except in directly quoted material, and even then include a footnote, a square-bracketed editor's note (such as ... 1360 bce [uncalibrated]), or other indication to the reader what the calibrated date is, or at least that the date is uncalibrated. Calibrated and uncalibrated dates can diverge surprisingly widely, and the average reader does not recognize the distinction between bce and BCE-BC.
      • Year ranges, like all ranges, are separated by an en dash: do not use a hyphen or slash (2005–08, not 2005-08 or 2005/08). A closing CE-AD year is normally written with two digits (1881–86) unless it is in a different century from that of the opening year (1881–1986). The full closing year is acceptable, but abbreviating it to a single digit (1881–6) or three digits (1881–886) is not. A closing BCE-BC year is given in full (2590–2550 BCE). While one era signifier at the end of a date range still requires an unspaced en dash (12–5 BC), a spaced en dash is required when a signifier is used after the opening and closing years (5 BC – 29 AD).
      • A slash may be used to indicate regular defined yearly periods that do not coincide with calendar years (the financial year 1993/94).
      • Abbreviations indicating long periods of time ago—such as BP (Before Present), as well as various annum-based units such as ka (kiloannum) and kya (thousand years ago), Ma (megaannum) and Mya (million years ago), and Ga (gigaannum or billion years ago)—are given as full words and wikilinked on first occurrence.
      • To indicate around, approximately, or about, the abbreviations c. and ca. are preferred over circa, approximately or approx., and are spaced (c. 1291). Use a question mark instead (1291?) only if the date is in fact questioned rather than approximate. (The question mark may mistakenly be understood as a sign that editors have simply not checked the date.)
  • Decades contain no apostrophe (the 1980s, not the 1980's); the two-digit form is used only where the century is clear (the '80s or the 80s).
  • Centuries and millennia are written using ordinal numbers, without superscripts and without Roman numerals: the second millennium, the 19th century, a 19th-century book (see also Numbers as figures or words below).

Numbers

Numbers as figures or words

As a general rule, in the body of an article, single-digit whole numbers from zero to nine are spelled out in words; numbers greater than nine are commonly rendered in numerals, or may be rendered in words if they are expressed in one or two words (16 or sixteen, 84 or eighty‑four, 200 or two hundred, but 3.75, 544, 21 million). This applies to ordinal numbers as well as cardinal numbers. However there are frequent exceptions to these rules.

  • Numerals are used in tables and infoboxes, and in places where space is limited. Numbers within a table's explanatory text and comments should be consistent with the general rule.
  • Comparable quantities should be all spelled out or all figures: we may write either 5 cats and 32 dogs or five cats and thirty‑two dogs, not five cats and 32 dogs.
  • Adjacent quantities that are not comparable should usually be in different formats: thirty‑six 6.4‑inch rifled guns is more readable than 36 6.4‑inch rifled guns.
  • Numbers that begin a sentence are spelled out, although it is often better to recast the sentence if simply changing format would produce other problems.
  • The numerical elements of dates and times are not normally spelled out, except where customary in historical references such as Seventh of March Speech.
  • Centuries are named in figures: (the 5th century CE; 19th‑century painting); when the adjective is hyphenated, consider nineteenth‑century painting, but not when contrasted with painting in the 20th century.
  • Simple fractions are normally spelled out; use the fraction form if they occur in a percentage or with an abbreviated unit (⅛ mm or an eighth of a millimeter) or if they are mixed with whole numbers. Decimal fractions are not spelled out.
  • Mathematical quantities, measurements, stock prices, etc., are normally stated in figures.
  • The use of words rather than figures may be preferred when expressing approximate numbers.
  • Proper names, idioms, and formal numerical designations comply with common usage (Chanel No. 5, 4 Main Street, 1‑Naphthylamine, Channel 6). This is the case even where it causes a numeral to open a sentence, although this is usually avoided by rewording.
  • Most proper names containing numbers spell them out (e.g. Fourth Amendment, Seventeenth Judicial District, Seven Years' War); the proper names of military units do not.

Large numbers

  • Commas are used to break the sequence every three places: 2,900,000.
  • Large rounded numbers are generally assumed to be approximations; only where the approximation could be misleading is it necessary to qualify with about or a similar term.
  • Avoid over-precise values where they are unlikely to be stable or accurate, or where the precision is unnecessary in the context. The speed of light in a vacuum is 299,792,458 metres per second is probably appropriate, but The distance from the Earth to the Sun is 149,014,769 kilometres and The population of Cape Town is 2,968,790 would usually not be, because both values are unstable at that level of precision, and readers are unlikely to care in the context.
  • Scientific notation like 6.02 × 1023 is preferred in scientific contexts.
  • Where values in the millions occur a number of times through an article, upper-case M may be used for million, unspaced, after using the full word at the first occurrence: She bequeathed her fortune of £100 million unequally: her eldest daughter received £70M, her husband £18M, and her three sons just £4M each.
  • Billion is understood as 109. After the first occurrence in an article, billion may be abbreviated to unspaced bn ($35bn).

Decimal points

  • A decimal point is used between the integral and the fractional parts of a decimal; a comma is never used in this role (6.57, not 6,57).
  • The number of decimal places should be consistent within a list or context (The response rates were 41.0 and 47.4 percent, respectively, not The response rates were 41 and 47.4 percent, respectively), except in the unusual instances where the items were measured with unequal precision.
  • Numbers between minus one and plus one require a leading zero (0.02, not .02); exceptions are performance averages in sports where a leading zero is not commonly used, and commonly used terms such as .22 caliber.

Percentages

  • Percent or per cent are commonly used to indicate percentages in the body of an article. The symbol % may be more common in scientific or technical articles, or in complex listings.
  • The symbol is unspaced (71%, not 71 %).
  • In tables and infoboxes, the symbol is used, not the words percent or per cent.
  • Ranges are preferably formatted with one rather than two percentage signifiers (22–28%, not 22%–28%).

Units of measurement

The use of units of measurement is based on the following principles:

  • Avoid ambiguity: Aim to write so you cannot be misunderstood.
  • Familiarity: The less one has to look up definitions, the easier it is to be understood.
  • International scope: Wikipedia is not country-specific; apart from US and some UK specific topics, use metric units.

If there is trouble balancing these bullets, consult other editors through the talk page and try to reach consensus.

Which units to use

  • In general, prefer units approved by the Bureau International des Poids et Mesures (BIPM). SI units, SI derived units, and non-SI units accepted for use with SI are preferred over other units, so 25 °C (77 °F) rather than 77 °F (25 °C).
    • UK-related topics may have either SI (generally preferred) or imperial units as the primary units.
    • In US-specific topics, the primary units are generally US customary units, with conversions given into SI and related units
  • Use units consistently. An article should have one set of primary units (e.g., write A 10 kg (22 lb) bag of potatoes and a 5 kg (11 lb) bag of carrots, not A 10 kg (22 lb) bag of potatoes and an 11 lb (5 kg) bag of carrots.
  • If editors cannot agree on the sequence of units, put the source value first and the converted value second. If the choice of units is arbitrary, use SI units as the main unit, with converted units in parentheses.
  • Use familiar units rather than obscure units—do not write over the heads of the readership (e.g., a general interest topic such as black holes would best be served by having mass expressed in solar masses, but it might be appropriate to use Planck units in an article on the mathematics of black hole evaporation).
  • Some disciplines use units not approved by the BIPM, or write them differently from BIPM-prescribed format. When a clear majority of the sources relevant to those disciplines uses such units, articles should follow this (e.g., using cc in automotive articles and not cm3). Such use of non-standard units are always linked on first use.
  • In scientific articles, use the units employed in the current scientific literature on that topic. This will usually be SI, but not always; for example, natural units are often used in relativistic and quantum physics, and Hubble's constant should be quoted in its most common unit of (km/s)/Mpc rather than its SI unit of s−1.
  • Avoid ambiguous unit names (e.g., write imperial gallon or US gallon rather than gallon). Only in the rarest of instances should ambiguous units be used, such as in direct quotations, to preserve the accuracy of the quotation.
  • American English uses -er endings for metric units: liter, kilometer; all other varieties of English, including Canadian, use -re: litre, kilometre.

Unit conversions

  • Generally, conversions to and from metric units and US or imperial units should be provided, except:
    • articles on scientific topics where there is consensus among the contributors not to convert the metric units, in which case the first occurrence of each unit should be linked;
    • where inserting a conversion would make a common expression awkward (The four-minute mile).
  • In the main text, give the main units as words and use unit symbols or abbreviations for conversions in parentheses; for example, a pipe 100 millimetres (4 in) in diameter and 16 kilometres (10 mi) long or a pipe 4 inches (100 mm) in diameter and 10 miles (16 km) long. However, where there is consensus to do so, the main units may also be abbreviated in the main text after the first occurrence.
  • Converted values should use a level of precision similar to that of the source value, so the Moon is 380,000 kilometres (240,000 mi) from Earth, not (236,121 mi). However, small numbers may need to be converted to a greater level of precision where rounding would cause a significant distortion, so one mile (1.6 km), not one mile (2 km).
  • Category:Conversion templates can be used to convert and format many common units, including {{convert}}, which includes non-breaking spaces.
  • In a direct quotation:
    • conversions required for units cited within direct quotations should appear within square brackets in the quote;
    • if the text contains an obscure use of units (five million board feet of lumber), annotate it with a footnote that provides standard modern units, rather than changing the text of the quotation.
  • Measurements should be accompanied by a proper citation of the source using a method described at the style guide for citation.
  • Where footnoting or citing sources for values and units, identify both the source and the original units.

Clarify ambiguous units

Unnecessary vagueness

Use accurate measurements whenever possible.

Vague Precise

The wallaby is small.

The average male wallaby is 1.6 metres (63 in) from head to tail.

Prochlorococcus marinus is a tiny cyanobacterium.

The cyanobacterium Prochlorococcus marinus is 0.5 to 0.8 micrometres across.

The large oil spill stretched a long way down the Alaskan coast.

The oil spill that drifted down the Alaskan coast was 3 statute miles (5 km) long and 1,000 feet (300 m) wide.

Unit symbols and abbreviations

  • Non-breaking spaces are used between values and unit symbols; see the Non-breaking spaces section above. (When values and spelled out units form a compound adjective, they are separated by a hyphen; see the Hyphens section above.)
  • Standard abbreviations and symbols for units are undotted (do not carry periods). For example, m for metre/meter and kg for kilogram (not m. or kg.), in for inch (not in.,  or ), ft for foot (not ft., or ) and lb for pound (not lb. or #).
  • The degree symbol is °. Using any other symbol (e.g., masculine ordinal º or "ring above" ˚) for this purpose is incorrect.
  • Do not append an s for the plurals of unit symbols (kg, km, in, lb, not kgs, kms, ins, lbs). A lowercase s is the SI symbol for second; thus, kgs can be confused with kg s, which means "kilogram-second".
  • Temperatures are always accompanied by °C for degrees Celsius, °F for degrees Fahrenheit, or K (but not °K) for kelvin. Further, a space—preferably a non-breaking space (&nbsp;)—always separates the value and temperature symbol (e.g. 35 °C, 62 °F, and 5,000 K.
  • In most cases, a space—preferably a non-breaking space (&nbsp;)—separates numeric values and unit symbols (25 kg, not 25kg). The exceptions are the percent symbol (%) and the symbols for degrees, minutes and seconds of plane angle (e.g. a 25% share, the coordinate is 5° 24′ 21.12″ N, and the pathways meet at a 90° angle).
  • Squared and cubic metric-symbols are always expressed with a superscript exponent (5 km2, 2 cm3); squared imperial and US unit abbreviations may be rendered with sq, and cubic with cu (15 sq mi, 3 cu ft).
  • Do not use the Unicode characters ² and ³, but rather write <sup>2</sup> and <sup>3</sup> to produce the superscripts 2 and 3. The superscripted 2 and 3 are easier to read, especially on small displays, and ensure that exponents are properly aligned (compare x1x²x³x4 vs x1x2x3x4).
  • In tables and infoboxes, use symbols and abbreviations for units, not words.
  • Ranges are preferably formatted with one rather than two unit signifiers (5.9–6.3 kg, not 5.9 kg – 6.3 kg).

Currencies

See Wikipedia:Manual of Style (dates and numbers)#Currencies

Common mathematical symbols

  • For a negative sign or subtraction operator, use a minus sign (), input by clicking on it in the insert box beneath the edit window or by typing &minus;; do not use a hyphen (-), unless writing code.
  • For a multiplication sign between numbers, use ×, which is input by clicking on it in the edit toolbox under the edit window or by typing &times;; do not use an asterisk (*), unless writing code. However, the unspaced letter x is accepted as a substitute for by in such terms as 4x4.
  • Exponentiation is indicated using a superscript, an (typed as a<sup>n</sup>); do not use a caret, a^n. Exponential notation can be spaced or unspaced, depending on circumstances; do not use E notation.
  • Symbols for binary operators and relations are spaced on both sides, including:
    • plus, minus, and plus-or-minus (as operators): +, , ±.
    • multiplication and division: ×, ÷.
    • equals, does not equal, equals approximately: =, , .
    • is less than, is less than or equal to, is greater than, is greater than or equal to: <, , >, .

Simple tabulation

Lines that start with blank spaces in the editing window are displayed boxed and in a fixed-width font, for simple tabulation. Lines that contain only a blank space insert a blank line into the table. For a complete guide to constructing tables, see Meta:Help:Table.

Grammar

Possessives

For thorough treatment of the English possessive see Apostrophe. See also Apostrophes, above.
  • It's is the short form of it is or it has (as in it's a nice day, it's been a nice day); the possessive its (as in the dog chased its tail) has no apostrophe, nor do hers, ours, yours, theirs, and whose.
  • The possessive of a singular noun is formed by adding 's (as in my daughter's achievement, the boss's wife, Glass's books, Illinois's legislature). For a singular noun ending in one s, there are two widely accepted forms:[5]
  • Add 's: James's house, Euripides's plays, Moses's early life, Brahms's music. This style is more common for modern names and common nouns.
  • Add just an apostrophe: James' house, Euripides' plays, Moses' early life, Brahms' music. This style is more common for biblical and classical names (Socrates' wife; Moses' ascent of Sinai; Jesus' last words).
Either of those forms may be acceptable in Wikipedia articles, as long as consistency is maintained within a given article. According to some it depends on perceived pronunciation, such as whether one would say James' house or James's house, but at least be consistent within an article.
  • The possessive of a plural noun ending in s is formed by adding just the apostrophe (my daughters' husbands). The possessive of a plural noun not ending in s is formed by adding 's (women's careers, children's toys).
  • Official names (of companies, organizations, or places) should be made to conform to a specific style.

First-person pronouns

Wikipedia articles must not be based on one person's opinions or experiences; thus, the pronoun I is never used, except when it appears in a quotation. For similar reasons, avoid the pronoun we; a sentence such as We should note that some critics have argued in favor of the proposal sounds more personal than encyclopedic. It is however acceptable to use we in historical articles to mean the modern world as a whole, as in The text of De re publica has come down to us with substantial sections missing.

Second-person pronouns

Use of the second person (you), which is often ambiguous and contrary to the tone of an encyclopedia, is discouraged. Instead, refer to the subject of the sentence or use the passive voice—for example:

Do not use:

When you move past "Go", you collect $200.

Use:

When a player moves past "Go", that player collects $200.

Use:

Players passing "Go" collect $200.

Use:

$200 is collected when passing "Go".

This guideline does not apply to quoted text, which should be quoted exactly.

Contested vocabulary

Words and phrases like thusly, overly, whilst, amongst, as per, refute in the sense of dispute, along with several others, should be avoided because they are not widely accepted—at least in some of their applications. Some are regional, so unsuitable in an international encyclopedia (see National varieties of English below). Some give an impression of "straining for formality", and therefore of an insecure grasp of English. See List of English words with disputed usage, Words to avoid, and List of commonly misused English words; see also Identity and Gender-neutral language below.

Contractions

In general, the use of contractions—such as don't, can't, won't, they'd, should've, it's—is informal and should be avoided; however, contractions should be left unchanged when they occur in a quotation.

Instructional and presumptuous language

Avoid such phrases as remember that and note that, which address readers directly in an unencyclopedic tone. Similarly, phrases such as of course, naturally, obviously, clearly and actually make presumptions about readers' knowledge, and call into question the reason for including the related information in the first place. See Wikipedia:Words to avoid.

Subset terms

A subset term identifies a set of members of a larger class. Common subset terms are including, among, and et cetera (etc.). Do not use two subset terms ("Among the most well-known members of the fraternity include ...", "The elements in stars include hydrogen, helium and iron, etc."). Do not use including to introduce a complete list, where comprising, consisting of, or composed of would be correct.

Plurals

Use the appropriate plural; allow for cases like oblast, or octopus, when a foreign word has been assimilated into English and normally takes an s or es plural, not its original plural. A number of words, like army, company, crowd, fleet, government, majority, mess, number, pack, and party may refer either to a single entity or the members of the set that compose it. In British English, they are normally treated as singular or plural according to context; names of towns and countries take plural verbs when they refer to sports teams but singular verbs when they refer to the actual place (or to the club as a business enterprise): England are playing Germany tonight refers to a football team, but England is the most populous country of the United Kingdom refers to the country.

In North American English, these words (and the United States, for historical reasons) are invariably treated as singular. See WP:ENGVAR.

Ampersand

The ampersand (&) is a symbol representing the word and. In running prose, and should mainly be used instead as it is more formal. If it appears in the titles of businesses, works, or in a quotation, the use of an ampersand is justified. The ampersand may also be used in tables, infoboxes, and other places where space is limited.

National varieties of English

The English Wikipedia does not prefer any major national variety of the language. No variety is more correct than another. Editors should recognize that the differences between the varieties are superficial. Cultural clashes over spelling and grammar are avoided by using the following four guidelines. (The accepted style of punctuation is covered in the punctuation section.)

Consistency within articles

See also Internal consistency

Each article should consistently use the same conventions of spelling, grammar, and punctuation. For example, these should not be used in the same article: center and centre; insofar and in so far; em dash and spaced en dash (see above). The exceptions are:

  • quotations (the original variety is retained; though the precise styling of punctuation marks such as dashes, ellipses, apostrophes, and quotation marks should be made consistent with the surrounding article);
  • proper names (the original spelling is used, for example United States Department of Defense and Australian Defence Force);
  • book titles (again, use the original spelling—if there are multiple editions which spell a given title differently, use the one consulted); and
  • explicit comparisons of varieties of English.

Strong national ties to a topic

An article on a topic that has strong ties to a particular English-speaking nation uses the appropriate variety of English for that nation. For example:

This is primarily intended to avoid the (unlikely) case in which an article that will be overwhelmingly read by one nationality has been written in another national dialect. Australians should not stumble over Americanisms in Australian Defence Force; Americans should not find Anglicisms in American Civil War.

Using an author's chosen variety of English may also be desirable in a biographical or critical article, especially if the author's writings are quoted in his article; some readers will be disconcerted by the shift between Tolkien's very English prose and another dialect, for example; however, some authors write in a mixture of national dialects.

This recommendation should not be used to claim national ownership of certain articles; see WP:OWN.

Retaining the existing variety

If an article has evolved using predominantly one variety, the whole article should conform to that variety, unless there are reasons for changing it based on strong national ties to the topic. In the early stages of writing an article, the variety chosen by the first major contributor to the article should be used. Where an article that is not a stub shows no signs of which variety it is written in, the first person to make an edit that disambiguates the variety is equivalent to the first major contributor.

Opportunities for commonality

Wikipedia tries to find words that are common to all varieties of English.

  • In choosing words or expressions, especially for article titles, there may be value in making choices that avoid varying spellings, where possible. In extreme cases of conflicting names, a common substitute (such as fixed-wing aircraft) is preferred to national varieties (fixed-wing aeroplanes [British English], and fixed-wing airplanes [American English]).
  • If a variable spelling appears in an article name, redirect pages are made to accommodate the other variants, as with Artefact and Artifact, so that they can always be found in searches and linked to from either spelling.
  • Sensitivity to terms that may be used differently between different varieties of English allows for wider readability; this may include glossing terms and providing alternative terms where confusion may arise. Insisting on a single term or a single usage as the only correct option does not serve well the purposes of an international encyclopedia.
  • Use an unambiguous word or phrase in preference to one that is ambiguous because of national differences. For example, use alternative route (or even other route) rather than alternate route, since alternate may mean only "alternating" to a British English speaker.

Articles such as English plural and American and British English differences provide information on the differences between the major varieties of the language.

Foreign terms

Foreign words should be used sparingly.

No common usage in English
Use italics for phrases in other languages and for isolated foreign words that are not current in English.
Common usage in English
Loanwords and borrowed phrases that have common usage in English—Gestapo, samurai, vice versa, esprit de corps—do not require italics. A rule of thumb is not to italicize words that appear unitalicized in major English-language dictionaries.
Spelling and transliteration

Names not originally in a Latin alphabet—such as Greek, Chinese or Cyrillic scripts—must be transliterated into characters generally intelligible to English-speakers. Do not use a systematically transliterated name if there is a common English form of the name, such as Tchaikovsky or Chiang Kai-shek.

The use of diacritics (accent marks) on foreign words is neither encouraged nor discouraged; their usage depends on whether they appear in verifiable reliable sources in English and on the constraints imposed by specialized Wikipedia guidelines. Place redirects at alternate titles, such as those without diacritics.

Within an article, spell a name that appears in the article title as in that title (covered in naming conventions) rather than an alternative spelling, unless there is a good reason to do so, such as may be given in Naming conventions (use English). Spell the other foreign names, phrases and words as most commonly spelled in the English-language references in an article, unless those spellings are idiosyncratic. If the foreign names, phrases or words do not appear in the article's references, then use the spelling as most commonly used in other verifiable reliable sources (for example other English-language dictionaries and encyclopedias). If the foreign phrase or word appears rarely in English, avoid using it.

Sometimes the usage will be influenced by other guidelines such as national varieties of English, which may lead to different usage in different articles.

Identity

  • Disputes over the proper name of a person or group are addressed by policies such as Verifiability, Neutral point of view, and Naming conventions where the name appears in an article name. When there is no dispute, the name most commonly used for a person will be the one that person uses for himself or herself, and the most common terms for a group will be those that the group most commonly uses for itself; Wikipedia should use them too.
  • A transgender, transsexual or genderqueer person's latest preference of name and pronoun should be adopted when referring to any phase of that person's life, unless this usage is overridden by that person's own expressed preference. Nevertheless, avoid confusing or seemingly logically impossible text that could result from pronoun usage (e.g., she fathered her first child).
  • Use specific terminology. For example, often it is more appropriate for people from Ethiopia (a country in Africa) to be described as Ethiopian, not carelessly (with the risk of stereotyping) as African.
  • Avoid the use of certain adjectives as nouns to refer to groups of people within society: use black people rather than blacks, gay people rather than gays, disabled people rather than the disabled, et cetera.
  • The term Arab (never to be confused with Muslim or Islamic) refers to people and things of ethnic Arab origin. The term Arabic refers to the Arabic language or writing system, and related concepts (Not all Arab people write or converse in Arabic.)
  • As always in a direct quotation, use the original text, even if the quoted text is inconsistent with the preceding guidelines.

Gender-neutral language

Use gender-neutral language where this can be done with clarity and precision. This does not apply to direct quotations or the titles of works (The Ascent of Man), or where all referents are of one gender, such as in an all-female school (if any student broke that rule, she was severely punished).

Images

  • Start an article with a right-aligned lead image or infobox.
  • Images should be inside the section they belong to (after the heading and after any links to other articles), and not above the heading.
  • Avoid sandwiching text between two images that face each other.
  • Use captions to explain the relevance of the image to the article (see Captions, below).
  • See this tutorial for how to group images and avoid "stack-ups".
  • It is often preferable to place images of faces so that the face or eyes look toward the text. Multiple images in the same article can be staggered right-and-left (for example: Timpani). However, images should not be reversed simply to resolve a conflict between these guidelines; doing so misinforms the reader for the sake of our layout preferences. If an image is reversed or otherwise substantially altered, there should be a clear advantage to the reader in doing so (for example, cropping a work of art to focus on a detail that is the subject of commentary), and the alteration must be noted in the caption.
  • Do not place left-aligned images directly below a subsection-level heading (=== or lower), as this sometimes disconnects the heading from the text that follows it. This can often be avoided by shifting left-aligned images down a paragraph or two.
  • Most pictures should be between 100 and 400 pixels wide. Generally, use the thumbnail option ("thumb"), which is available in the image markup. This results in a default width of 180 pixels (140 pixels if the "upright" option is used as well), although logged-in users can set a different default in their user preferences. As a rule, images should not be set to another size (that is, one that overrides the default). Where it is appropriate to select a particular size, images should generally be no more than 300 pixels wide, so that they can be comfortably displayed on 800x600 monitors. Where appropriate, the {{Wide image}} template can be used to fit an image into the width of the browser window (similarly, {{tall image}} may be used for abnormally tall images). Examples where size-forcing may be appropriate include:
  • Images with aspect ratios that are extreme or that otherwise distort or obscure the image
  • Detailed maps, diagrams, or charts
  • Images containing a lot of detail, if the detail is important to the article
  • Images in which a small region is relevant, but cropping to that region would reduce the coherence of the image
  • Lead images, which should usually be no larger than 300 pixels
  • Use {{Commons}} to link to more images on Commons, wherever possible. The use of galleries should be in keeping with Wikipedia's image use policy.
  • Editors are encouraged to add alt text to all images for which it seems reasonable, including math-mode equations. Alternative text describes the image for readers who cannot see the image, such as visually impaired readers or those using web-browsers that do not download images.
    • Instructions on adding alt text to equations and images can be found here. The Altviewer tool displays an article's alt text.
    • Alt text is not the same as captions: alt text describes the image for those who cannot see it, whereas captions are intended to explain or supplement an image that is visible. Therefore, alt text should not be redundant with the caption or the main text of the article. The guideline on this subject notes that an image need not have alt text if it is purely decorative, that is, if it conveys no additional information and nothing happens when you click on it. Editors should ask themselves how much sighted readers would lose if the picture were blanked, and how far that is describable in words. By default, no alt text is defined in images, provided that the thumb or frame parameter is included.

Avoid entering textual information as images

Textual information should be entered as text rather than as an image. Text in images is not searchable, and can be slow to download; the image is unlikely to be read as text by devices for the visually impaired. Text may be colored and decorated with CSS tags and templates. Even if the problems can be worked around, as by including a caption or internal information, editors should still consider whether fancy text really adds anything useful.

Captions

Usage

Photographs and other graphics should always have captions, unless they are "self-captioning" (such as reproductions of album or book covers) or when they are unambiguous depictions of the subject of the article. For example, in a biography article, a caption is not mandatory for a portrait of the subject pictured alone, but might contain the name of the subject and additional information relevant to the image, such as the year or the subject's age.

Formatting

  • Captions normally start with a capital letter.
  • Most captions are not complete sentences, but merely nominal groups (sentence fragments) that should not end with a period. If a complete sentence occurs in a caption, that sentence and any sentence fragments in that caption should end with a period.
  • Captions should not be italicized, except for words that are conventionally italicized.
  • Captions should be succinct; more information about the image can be included on its description page, or in the main text.

Bulleted and numbered lists

  • Do not use lists if a passage reads easily using plain paragraphs.
  • Do not leave blank lines between items in a bulleted or numbered list unless there is a reason to do so, since this causes the Wiki software to interpret each list item as an individual list.
  • Use numbers rather than bullets only if:
    • there is a need to refer to the elements by number;
    • the sequence of the items is critical; or
    • the numbering has value of its own, for example in a track listing.
  • Use the same grammatical form for all elements in a list where possible, and do not mix the use of sentences and sentence fragments as elements.
    • When the elements are complete sentences, they are formatted using sentence case and a final period.
    • When the elements are sentence fragments, they are typically introduced by a lead fragment ending with a colon. When these elements are titles of works, they retain the original capitalization of the title. Other elements are formatted consistently in either sentence or lower case. Final punctuation for these elements can be omitted entirely, or should otherwise be a period for the terminating element with each of its preceding elements having a final semicolon.

Links

Wikilinks

Make links only where they are relevant to the context: It is not useful and can be very distracting to mark all possible words as hyperlinks. Links should add to the user's experience; they should not detract from it by making the article harder to read. A high density of links can draw attention away from the high-value links that you would like your readers to follow up. Redundant links clutter the page and make future maintenance harder.

Check links: After linking, ensure that the destination is the intended one; many dictionary words lead to disambiguation pages and not to complete articles on a concept. An anchor into a targeted page—the label after a pound/hash sign (#) in a URL—will get readers to the relevant area within that page.

Initial capitalization: Wikipedia's MediaWiki software does not require that wikilinks begin with an upper-case character. Only capitalize the first letter where this is naturally called for, or when specifically referring to the linked article by its name: Snakes are often venomous, but lizards only rarely (see Poison).

External links

External links should not normally be used in the body of an article. Articles can include an external links section at the end to list links to websites outside Wikipedia that contain further information, as opposed to citing sources. The standard format is a primary heading named == External links == followed by a bulleted list of links. External links should identify the link and briefly indicate its relevance to the article subject. For example:

*[http://history.nih.gov/exhibits/history/index.html History of NIH]
*[http://www.nih.gov/ National Institutes of Health homepage]

These will appear as:

Avoid listing an excessive number of external links; Wikipedia is not a link repository.

Miscellaneous

Keep markup simple

Use the simplest markup to display information in a useful and comprehensible way. Markup may appear differently in different browsers. Use HTML and CSS markup sparingly and only with good reason. Minimizing markup in entries allows easier editing.

In particular, do not use the CSS float or line-height properties because they break rendering on some browsers when large fonts are used.

Formatting issues

Formatting issues such as font size, blank space and color are issues for the Wikipedia site-wide style sheet and should not be specified in articles except in special cases. If you absolutely must specify a font size, use a relative size like font-size: 80%, not an absolute size like font-size: 8pt. It is also almost never a good idea to use other style changes, such as font family or color.

Typically, the use of custom font styles will:

  • reduce consistency—the text will no longer look uniform;
  • reduce usability—it will likely be impossible for people with custom stylesheets (for accessibility reasons, for example) to override it, and it might clash with a different skin as well as bother people with color blindness; and
  • increase arguments—other Wikipedians may disagree aesthetically with the choice of style.

Color coding

Using color alone to convey information (color coding) should not be done. Such information is not accessible to people with color blindness, on black-and-white printouts, on older computer displays with fewer colors, on monochrome displays (PDAs, cell phones), and so on.

If it is necessary to use colors, try to choose colors that are unambiguous (such as orange and violet) when viewed by a person with red-green color blindness (the most common type). In general, this means that shades of red and green should not both be used as color codes in the same image. Viewing the page with Vischeck can help determine whether the colors should be altered.

It is certainly desirable to use color as an aid for those who can see it, but the information should still be accessible without it.

Scrolling lists

Scrolling lists and boxes that toggle text display between hide and show are acceptable in infoboxes and navigation boxes, but should never be used in the article prose or references, because of issues with readability, accessibility, and printing.

Invisible comments

Editors use invisible comments to communicate with each other in the body of the text of an article. These comments are visible only in the wiki source (that is, in edit mode), not in read mode.

Invisible comments are useful for flagging an issue or leaving instructions about part of the text, where this is more convenient than raising the matter on the talk page. They should be used judiciously, because they can clutter the wiki source for other editors. Check that your invisible comment does not change the formatting, such as introducing unwanted white space in read mode.

To leave an invisible comment, enclose the text you intend to be read only by editors within <!-- and -->. For example: <!--If you change this section title, please also change the links to it on the pages ...-->

Pronunciation

Pronunciation in Wikipedia is indicated using the International Phonetic Alphabet (IPA). For ease of understanding across dialects, fairly broad IPA transcriptions are usually provided for English pronunciations. See Wikipedia:IPA for English and Wikipedia:IPA (general) for keys, and {{IPA}} for templates that link to these keys. For English pronunciations, pronunciation respellings may be used in addition to the IPA.

Blazon

For heraldic terms written in Anglo-Norman (a form of Middle English), refer to WP:BLAZON. The key points are:

  • Anglo-Norman blazons should be put in italics.
  • Short extracts may be put in-line but longer ones should be indented on a new line (similar to quotations).
  • Tinctures should not be capitalized unless the first word of a blazon, except Or to distinguish it from the conjunction or. Charges need not be capitalized.
  • Tinctures may be repeated (e.g. "Or, on a bend gules a sword Or") or truncated (e.g. "Or, on a bend gules a sword of the first"), as it appears in the source.
  • Exceptions should be made if doing so is more appropriate to a blazon than following the guideline.

See also

Notes

  1. ^ Wikipedia:Requests_for_arbitration/Jguk#Principles, Wikipedia:Requests_for_arbitration/jguk_2#Principles, and Wikipedia:Requests_for_arbitration/Sortan#Principles
  2. ^ W3C Recommendation 26 January 2000, revised 1 August 2002 : Section C.8. Fragment Identifiers, World Wide Web Consortium.
  3. ^ The use of autoformatting links for dates is now deprecated. This refers to the system by which a date containing day, month and year can be surrounded by double square brackets to permit logged-in users to select a user preference for date formats.
  4. ^ Non-Gregorian dates are entirely forbidden by the standard, and use of years outside the range 1583 through 9999 require agreement of those receiving the information; no such agreement has been established with Wikipedia readers.
  5. ^ For details on these two forms and the rationale for their use, see Apostrophe. Evidence that this issue is largely unsettled among professional style guides and among Wikipedians can be found in the archives at WT:Manual_of_Style/Archive_92#Possessives of proper names ending in "s", WT:Manual_of_Style/Archive_100#Singular possessives ending in "s", WT:Manual_of_Style/Archive_102#Possessives, WT:Manual_of_Style/Archive_104#Possessive, and WT:Manual_of_Style/Archive_105#Possessives of common nouns in s.

Style guides on other Wikimedia projects

Further reading

Wikipedians are encouraged to familiarize themselves with other guides to style and usage, which may cover details that are not included in this Manual of Style. Among these are: