Wikipedia:Manual of Style
The Manual of Style (MoS or MOS) is the style manual for all English Wikipedia articles. This primary page is supported by further detail pages, which are cross-referenced here and listed at Wikipedia:Manual of Style/Contents. If any contradiction arises, this page always has precedence.
MoS presents Wikipedia's house style to assist its volunteer editors write and maintain articles with precise and consistent language, layout, and formatting. Since using plain English makes the encyclopedia easier and more intuitive to read, editors should avoid ambiguity, jargon, and vague or unnecessarily complex wording.
Where more than one style or format is acceptable under MoS, one should be used consistently within an article and should not be changed without good reason. Edit warring over optional styles is unacceptable.
New content added to this page should directly address a persistently recurring style issue.
Sometimes the MoS provides more than one acceptable style or gives no specific guidance. The Arbitration Committee has expressed the principle that "When either of two styles are [sic] acceptable it is inappropriate for a Wikipedia editor to change from one style to another unless there is some substantial reason for the change." If you believe an alternative style would be more appropriate for a particular article, discuss this at the article's talk page or—if it raises an issue of more general application or with the MoS itself—at Wikipedia talk:Manual of Style.
A title should be a recognizable name or description of the topic that is natural, sufficiently precise, concise, and consistent with those of related articles. If these criteria are in conflict, they should be balanced against one another.
For formatting guidance see the Wikipedia:Article titles § Article title format section, noting the following:
An article should begin with an introductory lead section—a concise summary of the article—which is never divided into sections sections.. The remainder of the article is typically divided into
Infoboxes, images, and related content in the lead section must be right-aligned.
If an article has at least four section headings, a navigable table of contents appears automatically, just after the lead.
As explained in detail in , optional appendix and footer sections may appear after the body of the article, in the following order:
Section headings should follow all the guidance for article titles (above), and should be presented in sentence case (Funding of UNESCO projects in developing countries), not title case (Funding of UNESCO Projects in Developing Countries).[a]
These restrictions are necessary to avoid technical complications, and are not subject to override by local consensus or Wikipedia:Ignore all rules.
Before changing a heading, consider whether you might be breaking existing links to it. If there are many links to the old title, create an anchor with that title to ensure that these still work. Similarly, when linking to a section, leave an invisible comment at the heading of the target section, naming the linking articles, so that if the heading is later altered these can be fixed. Combined example:
The above guidance about sentence case, redundancy, images, and questions also applies to headers of tables (and of table columns and rows). However, table headings can incorporate citations and may begin with, or be, numbers. Unlike page headings, table headers do not automatically generate link anchors. Aside from sentence case in glossaries, the heading advice also applies to the term entries in description lists. If using template-structured glossaries, terms will automatically have link anchors, but will not otherwise. Citations for description-list content go in the term or definition element, as needed.
The English Wikipedia prefers no national variety of English over any other. These varieties (for example American English or British English) differ in vocabulary (elevator vs. lift), spelling (center vs. centre), date formatting ("October 27, 2020" vs. "27 October 2020"), and occasionally grammar . Articles such as English plurals and Comparison of American and British English provide information about such differences.
Within a given article the conventions of one particular variety of English should be followed consistently. Exceptions include:
For an international encyclopedia, using vocabulary common to all varieties of English is preferable.
For assistance with specific terms, see or American and British English spelling differences; most dictionaries also indicate regional terms.
An article on a topic that has strong ties to a particular English-speaking nation should use the (formal, not colloquial) English of that nation. For example:
For topics with strong ties to Commonwealth of Nations countries and other former British territories, use Commonwealth English orthography, largely indistinguishable from British English in encyclopedic writing (excepting Canada, which uses a different orthography).
When an English variety's consistent usage has been established in an article, maintain it in the absence of consensus to the contrary. With few exceptions (e.g., when a topic has strong national ties or the change reduces ambiguity), there is no valid reason for changing from one acceptable option to another.
When no English variety has been established and discussion does not resolve the issue, use the variety found in the first post-stub revision that introduced an identifiable variety. The established variety in a given article can be documented by placing the appropriate Varieties of English template on its talk page.
Wikipedia article titles and section headings use sentence case, not title case; see Wikipedia:Article titles and § Section headings. For capitalization of list items, see § Bulleted and numbered lists. Other points concerning capitalization are summarized below; full information can be found at Wikipedia:Manual of Style/Capital letters. The central point is that Wikipedia does not capitalize something unless it is consistently capitalized in a substantial majority of independent, reliable sources.
Generally, do not capitalize the word the in mid-sentence: throughout the United Kingdom, not throughout The United Kingdom. Conventional exceptions include certain proper names (he visited The Hague) and most titles of creative works (Tolkien wrote The Lord of the Rings—but be aware that the may not be part of the title itself, e.g. Homer composed the Odyssey).
The English-language titles of compositions (books and other print works, songs and other audio works, films and other visual media works, paintings and other artworks, etc.) are given in title case, in which every word is given an initial capital except for certain less important words (as detailed at ). The first and last words in an English-language title are always capitalized.
Capitalization in foreign-language titles varies, even over time within the same language; generally, retain the style of the original for modern works, and follow the usage in current[f] English-language reliable sources for historical works. Many of these items should also be in italics, or enclosed in quotation marks.
When using taxonomic ("scientific") names, capitalize and italicize the genus: Berberis, Erithacus. (Supergenus and subgenus, when applicable, are treated the same way.) Italicize but do not capitalize taxonomic ranks at the level of species and below: Berberis darwinii, Erithacus rubecula superbus, Acacia coriacea subsp. sericophylla; no exception is made for proper names forming part of scientific names. Higher taxa (order, family, etc.) are capitalized in Latin (Carnivora, Felidae) but not in their English equivalents (carnivorans, felids); they are not italicized in either form, except for viruses, where all names accepted by the ICTV are italicized (Retroviridae).
Cultivar and cultivar group names of plants are not italicized, and are capitalized (including the word Group in the name); cultivar names appear within single quotes (Malus domestica 'Red Delicious'), while cultivar groups do not (Cynara cardunculus Scolymus Group).
English vernacular ("common") names are given in lower case in article prose (plains zebra, mountain maple, and southwestern red-tailed hawk) and in sentence case at the start of sentences and in other places where the first letter of the first word is capitalized.[a] They are additionally capitalized where they contain proper names: Przewalski's horse, California condor, and fair-maid-of-France. This applies to species and subspecies, as in the previous examples, as well as to general names for groups or types of organism: bird of prey, oak, great apes, Bryde's whales, livestock guardian dog, poodle, Van cat, wolfdog. When the common name coincides with a scientific taxon, do not capitalize or italicize, except where addressing the organism taxonomically: Non-English vernacular names, when relevant to include, are handled like any other foreign-language terms: italicized as such, and capitalized only if the rules of the native language require it. Non-English names that have become English-assimilated are treated as English (ayahuasca, okapi).A lynx is any of the four medium-sized wild cat species within the genus Lynx.
Standardized breeds should generally retain the capitalization used in the breed standards.[g] Examples: German Shepherd dog, Russian White goat, Berlin Short-faced Tumbler. As with plant cultivars, this applies whether or not the included noun is a proper name, in contrast to how vernacular names of species are written. However, unlike cultivars, breeds are never put in single quotation marks, and their names are never part of a scientific name. A species term appended at the end for disambiguation ("cat", "hound", "horse", "swine", etc.) should not be capitalized, unless it is a part of the breed name itself and is consistently presented that way in the breed standard(s) (rare cases include Norwegian Forest Cat and American Quarter Horse).
Create redirects from alternative capitalization and spelling forms of article titles, and from alternative names, e.g., Adélie Penguin, Adelie penguin, Adelie Penguin and Pygoscelis adeliae should all redirect to Adélie penguin.
Do not capitalize directions such as north, or their related forms (We took the northern road), except where they are parts of proper names (Great North Road, Great Western Drive, South Pole).
Capitalize names of regions if they have attained proper-name status, including informal conventional names (Southern California; the Western Desert), and derived terms for people (e.g., a Southerner as someone from the Southern United States). Do not capitalize descriptive names for regions that have not attained the status of proper names, such as southern Poland.
Composite directions may or may not be hyphenated, depending on the variety of English adopted in the article. Southeast Asia and northwest are more common in American English; but South-East Asia and north-west in British English. In cases such as north–south dialogue and east–west orientation, use an en dash; see § En dashes: other uses.
Capitalize names of particular institutions (the founding of the University of Delhi; the history of Stanford University) but not generic words for institutions (the high school is near the university). Do not capitalize the at the start of an institution's name, regardless of the institution's preferred style. There are rare exceptions, when a leading The is represented by a T in the organization's acronym: The International Cat Association (TICA).
Treat political or geographic units similarly: The city has a population of 55,000; The two towns merged to become the City of Smithville. Do not mimic the style of local newspapers which refer to their municipality as the City or The City; an exception is the City of London, referred to as the City in a context that already makes the subject clear, as distinct from London and Greater London. When in doubt, use the full name for accessibility reasons; users of screen readers for the blind cannot hear a difference between city and City.
Ligatures should be used in languages in which they are standard (hence Moreau's last words were clin d'œil is preferable to Moreau's last words were clin d'oeil) but not in English (encyclopedia or encyclopaedia, not encyclopædia), except in proper names (Æthelstan not Aethelstan).
Abbreviations are shortened forms of words or phrases. In strict analysis, they are distinct from contractions, which use an apostrophe (e.g., won't, see § Contractions), and initialisms. An initialism is formed from some or all of the initial letters of words in a phrase. Below, references to abbreviations should be taken to include acronyms, and the term acronym to apply also to initialisms.Write out both the full version and the abbreviation at first occurrence
When an abbreviation will be used in an article, first introduce it using the full expression:an early local area network (LAN) developed by Digital Equipment Corporation (DEC) ... DEC's later LAN products were ...
Do not use capitals in the full version merely because capitals are used in the abbreviation: an early Local Area Network (LAN).
Except in special circumstances, common abbreviations (such as PhD, DNA, USSR) need not be expanded even on first use.
Pluralize acronyms by adding -s or -es: Three CD-ROMs and two BIOSes were released. (Do not use apostrophes to form plurals: Three CD-ROM's and two BIOS's were released.)
An abbreviation may or may not be terminated with a full point (also called a period or stop). A consistent style should be maintained within an article. North American usage is typically to end all abbreviations with a period/point (Dr. Smith of 42 Drummond St.) but in common British and Australian usage, no period/point is used if the abbreviation (contraction) ends in the last letter of the unabbreviated form (Dr Smith of 42 Drummond St) unless confusion could result. This is also common practice in scientific writing. Regardless of punctuation, words that are abbreviated to more than one letter are spaced (op. cit. not op.cit. or opcit). There are some exceptions: PhD for "Philosophiae Doctor"; BVetMed for "Bachelor of Veterinary Medicine". In most situations, Wikipedia : GDP, not G.D.P.
While, in principle, either US or U.S. may be used (with internal consistency) to abbreviate "United States" in any given article, the use or non-use of periods (full stops) should also be consistent with other country abbreviations in the same article (thus the US, UK, and USSR, not the U.S., UK, and USSR). In longer abbreviations (three letters or more) that incorporate the country's initials (USN, USAID), do not use periods. When the United States is mentioned with one or more other countries in the same sentence, U.S. or US may be too informal, especially at the first mention or as a noun instead of an adjective (France and the United States, not France and the U.S.). Do not use the spaced U. S. or the archaic U.S. of A., except when quoting; and do not use U.S.A. or USA except in a quotation, as part of a proper name (Team USA), or in certain technical or formal uses (e.g., the ISO 3166-1 alpha-3 codes and FIFA country codes).
Avoid abbreviations when they might confuse the reader, interrupt the flow, or appear informal. For example:
Generally avoid devising new abbreviations, especially acronyms. For example, World Union of Billiards is good as a translation of Union Mondiale de Billard, but neither it nor the reduction WUB is used by the organization or by independent sources; use the original name and its official abbreviation, UMB.
If it is necessary to abbreviate in a tight space, such as a column header in a table, use widely recognized abbreviations. For example, for New Zealand gross national product, use NZ and GNP, with a link if the term has not already been written out in the article: NZ GNP. Do not make up initialisms such as NZGNP.
In normal text and headings, use and instead of the ampersand (&): January 1 and 2, not January 1 & 2. But retain an ampersand when it is a legitimate part of the style of a proper noun, such as in Up & Down or AT&T. Elsewhere, ampersands may be used with consistency and discretion where space is extremely limited (e.g. tables and infoboxes). Quotations may be cautiously modified, especially for consistency where different editions are quoted, as modern editions of old texts routinely replace ampersands with and (just as they replace other disused glyphs, ligatures, and abbreviations).
Use italics for the titles of works (such as books, films, television series, named exhibitions, computer games, music albums, and paintings). The titles of articles, chapters, songs, episodes, research papers and other short works instead take double quotation marks. Italics are not used for major religious works (the Bible, the Quran, the Talmud). Many of these titles should also be in title case.
Use italics when mentioning a word or character the term panning is derived from panorama; the most common letter in English is e). When a whole sentence is mentioned, double quotation marks may be used instead, with consistency (The preposition in She sat on the chair is on; or The preposition in "She sat on the chair" is "on"). Quotation marks may also be used for shorter material to avoid confusion, such as when italics are already being heavily used in the page for some other purpose (e.g. many non-English words and phrases). Mentioning (to discuss grammar, wording, punctuation, etc.) is different from quoting (in which something is usually expressed on behalf of a quoted source). Quotation is done with quotation marks, never italics, nor both at onceor a string of words up to one sentence (
A closely related use of italics is when introducing or distinguishing terms: The natural numbers are the integers greater than 0.
Use italics for phrases in other languages and for isolated foreign words that are not common in everyday English. However, proper names (such as place names) in other languages are not usually italicized, nor are terms in non-Latin scripts.
Use italics for the scientific names of plants, animals, and all other organisms except viruses at the genus level and below (italicize Panthera leo and Retroviridae, but not Felidae). The hybrid sign is not italicized (Rosa × damascena), nor is the "connecting term" required in three-part botanical names (Rosa gallica subsp. officinalis).
Do not use italics for quotations. Instead, use quotation marks for short quotations and block quoting for long ones.
Use italics within quotations to reproduce emphasis that exists in the source material. If it is not clear that the source already included italics (or some other styling) for emphasis, add the editorial note [emphasis in original] after the quotation.
If adding emphasis that was not in the original, add the editorial note [emphasis added] after the quotation.
Italicize only the elements of the sentence affected by the emphasis. Do not italicize surrounding punctuation.
For a link to function, any italics markup must be either completely outside the link markup, or in the link's "piped" portion.
Brief quotations of copyrighted text may be used to illustrate a point, establish context, or attribute a point of view or idea. While quotations are an indispensable part of Wikipedia, try not to overuse them. Using too many quotes is incompatible with an encyclopedic writing style and may be a copyright infringement. It is generally recommended that content be written in Wikipedia editors' own words. Consider paraphrasing quotations into plain and concise text when appropriate (while being aware that close paraphrasing can still violate copyright).
In direct quotations, retain dialectal and archaic spellings, including capitalization (but not archaic glyphs and ligatures, as detailed below).
Quotation should be used, with attribution, to present emotive opinions that cannot be expressed in Wikipedia's own voice, but never to present cultural norms as simply opinional:
Concise opinions that are not overly emotive can often be reported with attribution instead of direct quotation. Use of quotation marks around simple descriptive terms can imply something doubtful regarding the material being quoted; sarcasm or weasel words such as supposedly or so-called, might be inferred.
A quotation is not a facsimile and, in most cases, it is not a requirement that the original formatting be preserved. Formatting and other purely typographical elements of quoted text should be adapted to English Wikipedia's conventions without comment provided that doing so will not change or obscure meaning or intent of the text. These are alterations which make no difference when the text is read aloud, for example:The cynical response "L'auteur aurait dû demander: « à quoi sert-il d'écrire ceci? » mais ne l'a pas fait" was all he wrote.
However, national varieties should not be changed, as these may involve changes in vocabulary. For example, a quotation from a British source should retain British spelling, even in an article that otherwise uses American spelling. should not be reformatted.Numbers also usually
Direct quotation should not be used to preserve the formatting preferred by an external publisher (especially when the material would otherwise be unchanged), as this tends to have the effect of "scare-quoting":
When quoting a complete sentence, it is usually recommended to keep the first word capitalized. However, if the quoted passage has been integrated into the surrounding sentence (for example, with an introduction such as "X said that"), the original capital letter may be lower-cased.
It is not normally necessary to explicitly note changes in capitalization. However, for more precision, the altered letter may be put inside square brackets: "The" → "[t]he".
The reader must be able to determine the source of any quotation, at the very least via a footnote. The source must be named in article text if the quotation is an opinion characterizing it in a biased manner.. When attributing a quotation, avoid
Be conservative when linking within quotations: link only to targets that correspond to the meaning clearly intended by the quote's author. Where possible, link from text outside of the quotation instead – either before it or soon after. (If quoting hypertext, add an editorial note, [link in original] or [link added], as appropriate, to avoid ambiguity as to whether the link was made by the original author.)
What this grim, ungainly, ghastly, gaunt, and ominous bird of yore
Meant in croaking "Nevermore."
Quotations from foreign-language sources should appear with a translation into English, preferably a modern[f] one. Quotations that are translations should be explicitly distinguished from those that are not. Indicate the original source of a translation (if it is available, and not first published within Wikipedia), and the original language (if that is not clear from the context).
If the original, untranslated text is available, provide a reference for it or include it, as appropriate.
When editors themselves translate foreign text into English, care must always be taken to include the original text, in italics (except for non-Latin-based writing systems), and to use actual and (if at all possible) common English words in the translation. Unless you are certain of your competency to translate something, see Wikipedia:Translation for assistance.
In the material below, the term quotation includes conventional uses of quotation marks such as for titles of songs, chapters, episodes, and so on. Quotation marks are also used in other contexts, such as in cultivar names.
Most quotations take double quotation marks (Bob said: "Jim ate the apple.").[h] Exceptions:
The use of a comma before a quotation embedded within a sentence is optional, if a non-quoted but otherwise identical construction would work grammatically without the comma:
A comma is required when it would be present in the same construction if none of the material were a quotation:
It is clearer to use a colon to introduce a quotation if it forms a complete sentence, and this should always be done for multi-sentence quotations:
No additional punctuation is necessary for an explicit words-as-words scenario:
On the English Wikipedia, use the "logical quotation" style in all articles, regardless of the variety of English in which they are written. Include terminal punctuation within the quotation marks only if it was present in the original material, and otherwise place it after the closing quotation mark. For the most part, this means treating periods and commas in the same way as question marks: keep them inside the quotation marks if they apply only to the quoted material and outside if they apply to the whole sentence. Examples are given below.
If the quotation is a single word or a sentence fragment, place the terminal punctuation outside the closing quotation mark. When quoting a full sentence, the end of which coincides with the end of the sentence containing it, place terminal punctuation inside the closing quotation mark.
If the quoted sentence has been broken up with an editorial insertion, still include the terminal punctuation inside the closing quotation mark.
If the quoted sentence is followed by a clause that should be preceded by a comma, omit the full stop (period) – but other terminal punctuation, such as a question mark or exclamation mark, may be retained.
If the quoted sentence is followed by a clause identifying the speaker, use a comma outside the quotation mark instead of a full stop inside it, but retain any other terminal punctuation, such as question marks.
Do not follow quoted words or fragments with commas inside the quotation marks, except where a longer quotation has been broken up and the comma is part of the full quotation.
This section applies to both round brackets ( ), often called parentheses, and square brackets [ ].
If a sentence contains a bracketed phrase, place the sentence punctuation outside the brackets (as shown here). However, where one or more sentences are wholly inside brackets, place their punctuation inside the brackets. There should be no space next to the inner side of a bracket. An opening bracket should usually be preceded by a space. This may not be the case if it is preceded by an opening quotation mark, another opening bracket, or a portion of a word:
There should be a space after a closing bracket, except where a punctuation mark follows (though a spaced dash would still be spaced after a closing bracket) and in unusual cases similar to those listed for opening brackets.
Avoid adjacent sets of brackets. Either put the parenthetic phrases in one set separated by commas, or rewrite:
Square brackets are used to indicate editorial replacements and insertions within quotations, though this should never alter the intended meaning. They serve three main purposes:
If a sentence includes subsidiary material enclosed in square or round brackets, it must still carry terminal punctuation after those brackets, regardless of any punctuation within the brackets.She refused all requests (except for basics such as food, medicine, etc.).
However, if the entire sentence is within brackets, the closing punctuation falls within the brackets. (This sentence is an example.)
<nowiki> markup can also be used:
If a URL itself contains square brackets, the wiki-text should use the URL-encoded form
https://example.com/foo.php?query=%5Bxxx%5Dyyy, rather than ...
query=[xxx]yyy. This will avoid truncation of the link after
A serial comma is a comma used immediately before a conjunction (and, or, nor) in a list of three or more items.
Editors may use either convention so long as each article is internally consistent; however, there are cases in which either omitting or including the serial comma results in ambiguity:
A colon (:) introduces something which demonstrates, explains, or modifies what has come before, or is a list of items that has 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 .
In most cases a colon works best with a complete grammatical sentence before it. When what follows the colon is also a complete sentence, start it with a capital letter, but otherwise do not capitalize after a colon except where doing so is needed for another reason, usually for a proper name.
There are exceptional cases, such as those where the colon introduces items set off in new lines. Examples:[j]
Except in technical usage (a 3:1 ratio), no sentence should contain multiple colons, no space precedes a colon, and a space (but never a hyphen or dash) follows a colon.
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 the semicolon separates clauses, normally each clause must be independent (meaning that it could stand on its own as a sentence). In many cases, only a comma or only a semicolon will be correct in a given sentence.
Above, "Though he had been here before" cannot stand on its own as a sentence, and therefore is not an independent clause.
This incorrect use of a comma between two independent clauses is known as a comma splice; however, in certain kinds of cases a comma may be used where a semicolon would seem to be called for:
A sentence may contain several semicolons, especially when the clauses are parallel in construction and meaning; multiple unrelated semicolons are often signs that the sentence should be divided into shorter sentences or otherwise refashioned.
Semicolons are used in addition to commas to separate items in a listing, when commas alone would result in confusion.
The meaning of a sentence containing a trailing clause that starts with the word however depends on the punctuation preceding that word. A common error is to use the wrong punctuation, thereby changing the meaning to one not intended.
When the word however is an adverb meaning "nevertheless", it should be preceded by a semicolon and followed by a comma. Example:
When the word however is a conjunction meaning "in whatever manner", or "regardless of how", it may be preceded by a comma but not by a semicolon, and should not be followed by punctuation. Example:
In the first case, the clause that starts with "however" cannot be swapped with the first clause; in the second case this can be done without change of meaning:
A sentence or clause can also contain the word however in the middle, if it is an adverb meaning "although" that could have been placed at the beginning but does not start a new clause in mid-sentence. In this use, the word may be enclosed between commas. Example:
Multi-word hyphenated items: It is often possible to avoid multi-word hyphenated modifiers 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).
For optional hyphenation of compound points of the compass such as southwest/south-west, see § Compass points.
Do not use a capital letter after a hyphen except for a proper name: Graeco-Roman and Mediterranean-style, but not Gandhi-Like. In titles of published works, follow the capitalization rule for each part independently (resulting in, e.g., The Out-of-Towners), unless reliable sources consistently do otherwise in a particular case (The History of Middle-earth).
Hyphenation rules in other languages may be different. Thus, in French a place name such as Trois-Rivières ("Three Rivers") is hyphenated, when it would not be in English. Follow reliable sources in such cases.
Spacing: A hyphen is never followed or preceded by a space, except when hanging sub- and the suffix -less.or when used to display parts of words independently, such as the prefix
Image filenames and redirects: Image filenames are not part of the encyclopedic content; they are tools. They are most useful if they can be readily typed, so they always use hyphens instead of dashes. Similarly, article titles with dashes should also have a corresponding redirect from a copy of the title with hyphens: for example, Michelson-Morley experiment redirects to Michelson–Morley experiment.
Encoding: The hyphen is represented by the ASCII/UNICODE HYPHEN-MINUS character, which is entered by the hyphen or minus key on all standard computer keyboards. Do not use the UNICODE HYPHEN character.
Hyphenation involves many subtleties that cannot be covered here; the rules and examples presented above illustrate the broad principles.
Two forms of dash are used on Wikipedia: en dash (–) and em dash (—). To enter them, click on them in the CharInsert toolbar to the right of the "Insert" dropdown beneath the edit window (in the Monobook Skin), or enter them manually as
—, respectively. Do not use a double hyphen (
--) to stand in for a dash.
Sources use dashes in varying ways. For consistency and clarity, Wikipedia adopts the following principles.
In article titles, do not use a hyphen (-) as a substitute for an en dash, for example in eye–hand span (since eye does not modify hand). Nonetheless, to aid searching and linking, provide a redirect with hyphens replacing the en dash(es), as in eye-hand span. Similarly, provide category redirects for categories containing dashes.
Dashes are often used to mark divisions within a sentence: in pairs (parenthetical dashes, instead of parentheses or pairs of commas); or singly (perhaps instead of a colon). They may also indicate an abrupt stop or interruption, in reporting quoted speech. In all these cases, use either unspaced em dashes or spaced en dashes, with consistency in any one article:Another "planet" was detected—but it was later found to be a moon of Saturn.Another "planet" was detected – but it was later found to be a moon of Saturn.
But do not insert a non-breaking or other space where the en dash should be unspaced.
Dashes can clarify the sentence structure when there are already commas or parentheses, or both.
Use dashes sparingly. More than two in a single sentence makes the structure unclear; it takes time for the reader to see which dashes, if any, form a pair.
If negative values are involved, an unspaced en dash might be confusing:In compounds when the connection might otherwise be expressed with to, versus, and, or between
Here, the relationship is thought of as parallel, symmetric, equal, oppositional, or at least involving separate or independent elements. The components may be nouns, adjectives, verbs, or any other independent part of speech. Often, if the components are reversed there would be little change of meaning.
Generally, use a hyphen in compounded proper names of single entities.
An en dash between separate nations; for people and things identifying with multiple nationalities, use a hyphen when applied as an adjective or a space as a noun.
A slash or some other alternative may occasionally be better to express a ratio, especially in technical contexts.
Use an en dash for the names of two or more entities in an attributive compound.
Do not use an en dash for hyphenated personal names, even when they are used as adjectives:Instead of a hyphen, when applying a prefix or suffix to a compound that includes a space or a dash
Spaced en dashes are sometimes used between parts of list items. For example:
The en dash (–) has other roles, beyond its use as a sentence-punctuating dash . It is often analogous to the hyphen , which joins components more strongly than the en dash; or to the slash , which separates alternatives more definitely. Consider the exact meaning when choosing which to use.
An indented em dash may be used before a name or other source when attributing below a block quotation, poem, etc. This dash should not be fully spaced, though it is best for metadata and accessibility reasons to hair-space it from the name.[m] Most of Wikipedia's quotation templates with attribution-related parameters already provide this formatting.
Do not use typewriter approximations or other substitutes, such as two hyphens (--), for em or en dashes.
For a negative sign or subtraction operator use U+2212 −
MINUS SIGN (HTML
−), which can also be generated by clicking on the
− following the
± in the Insert toolbar beneath the edit window. Do not use
U+2212 − inside a
<math> tag, as the character gives a syntax error; instead use a normal hyphen
U+002D - .
Generally, avoid joining two words with a slash, also called a forward slash, stroke or solidus ( / ), because it suggests that the words are related without specifying how. 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 the digital–analog distinction.is usually preferable to the slash:
Avoid writing and/or unless other constructions would be lengthy or awkward. Instead of Most had trauma and/or smoke inhalation, write simply trauma or smoke inhalation (which would normally be interpreted as an inclusive-or to imply or both); or, for emphasis or precision or both, write trauma or smoke inhalation or both. Where more than two possibilities are present, instead of x, y, and/or z write one or more of x, y, and z or some or all of x, y, and z.
Avoid using the # symbol (known as the number sign, hash sign, pound sign, or octothorpe) when referring to numbers or rankings. Instead write number, No. or Nos.; do not use the symbol №. For example:
In normal text, never put a space before a comma, semicolon, colon, period/full stop, question mark, or exclamation mark (even in quoted material; see § Typographic conformity).
Some editors type two spaces after a period/full stop; these are condensed to one when the page is rendered, so what the reader sees is not affected –.
Where a word or phrase that includes terminal punctuation ends a sentence, do not add a second terminal punctuation mark. If a quoted phrase or title ends in a question mark or exclamation mark, it may confuse readers as to the nature of the article sentence containing it, and so is usually better reworded to be mid-sentence. Where such a word or phrase occurs mid-sentence, new terminal punctuation (usually a period) must be added at the end.
Exceptions: Ref tags are placed before dashes, not after. Where a footnote applies only to material within parentheses, the ref tags belong just before the closing parenthesis.
A sentence that ends with a formula should have terminal punctuation (period, exclamation mark, or question mark) after the formula. Within a sentence, place other punctuation (such as commas or colons) after the formula just as if the text were not a formula. See .
Dates should be linked only when they are germane and topical to the subject, as discussed at .
Full dates are formatted 10 June 1921 or June 10, 1921; or where the year is omitted, use 10 June or June 10.
More information on all the above topics can be found at , including the handling of dates expressed in different calendars, and times corresponding to different time zones.
For the possessive of singular nouns, including proper names and words ending in s, add 's (my daughter's achievement, my niece's wedding, Cortez's men, the boss's office, Glass's books, Illinois's largest employer, Descartes's philosophy, Verreaux's eagle). Exception: abstract nouns ending with an /s/ sound, when followed by sake (for goodness' sake, for his conscience' sake). If a name ending in s or z would be difficult to pronounce with 's added (Jesus's teachings), consider rewording (the teachings of Jesus).
Official names (of companies, organizations, or places) should not be altered. (St Thomas' Hospital should therefore not be rendered as St Thomas's Hospital or St. Thomas Hospital, even for consistency.)
To maintain an objective and impersonal encyclopedic voice, an article should never refer to its editors or readers using I, my, we, us, or similar forms: We note that some have argued against our proposal. But some such forms are acceptable in certain figurative uses. For example:
Avoid addressing the reader using you or your, which sets an inappropriate tone.
Use the appropriate plural; allow for cases (such as excursus or hanif) in which a word is now listed in major English dictionaries, and normally takes an s or es plural, not its original plural: two excursuses, not two excursus as in Latin; two hanifs, not two hanufa as in Arabic.
Some collective nouns – such as team (and proper names of them), army, company, crowd, fleet, government, majority, mess, number, pack, and party – may refer either to a single entity or to the members that compose it. In British English, such words are sometimes treated as singular, but more often treated as plural, according to context. Exceptionally, names of towns and countries usually take singular verbs (unless they are being used to refer to a team or company by that name, or when discussing actions of that entity's government). For example, in England are playing Germany tonight, England refers to a football team; but in England is the most populous country of the United Kingdom, it refers to the country. In North American English, these words (and the United States, for historical reasons) are almost invariably treated as singular; the major exception is when sports teams are referred to by nicknames, plural verbs are commonly used to match e.g. the Heat are playing the Lakers. See also § National varieties of English.
By default, write articles in the present tense, including those covering works of fictionand products or works that have been discontinued. However, articles about periodicals that are no longer being produced should normally, and with commonsense exceptions, use the past tense. Generally, do not use past tense except for past events, subjects that are dead or no longer meaningfully exist, or periodicals and similar written material that are no longer being produced.
Tense can be used to distinguish between current and former status of a subject: (Emphasis added.)Dún Aonghasa is the ruin of a prehistoric Irish cliff fort. Its original shape was presumably oval or D-shaped, but parts of the cliff and fort have since collapsed into the sea.
Avoid contractions, which have little place in formal writing. For example, write cannot instead of can't. Use of o'clock is an exception. Contracted titles such as Dr. and St generally should not be used but may apply in some contexts (e.g. quoted material, place names, titles of works).
Use gender-neutral language – avoiding the generic he and generic she, for example – 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), which should not be altered, or to wording about one-gender contexts, such as an all-female school (When any student breaks that rule, she loses privileges).
References to space programs, past, present and future, should use gender-neutral phrasing: human spaceflight, robotic probe, uncrewed mission, crewed spacecraft, piloted, unpiloted, astronaut, cosmonaut, not manned or unmanned. Direct quotations and proper nouns that use gendered words should not be changed, like Manned Maneuvering Unit.
Ships may be referred to using either neuter forms ("it", "its") or feminine forms ("she", "her", "hers"). Either usage is acceptable, but each article should be internally consistent and employ one or the other exclusively. As with all optional styles, articles should not be changed from one style to another unless there is a substantial reason to do so. See .
Avoid words and phrases that give the impression of straining for formality, that are unnecessarily regional, or that are not widely accepted. See List of English words with disputed usage and Wikipedia:List of commonly misused English words; see also § Identity.
Avoid such phrases as remember that and note that, which address readers directly in an unencyclopedic tone and lean toward instructional. They are a subtle form of Wikipedia self-reference, "breaking the fourth wall". Similarly, phrases such as of course, naturally, obviously, clearly, and actually make presumptions about readers' knowledge, may express a viewpoint, and may call into question the reason for including the information in the first place. Do not tell readers that something is ironic, surprising, unexpected, amusing, coincidental, etc. Simply state the sourced facts and allow readers to draw their own conclusions. Such constructions can usually just be deleted, leaving behind proper sentences with a more academic and less pushy tone: becomes This was subject to controversy in more conservative newspapers.Note that this was naturally subject to controversy in more conservative newspapers.
Avoid rhetorical questions, especially in headings. Use a heading of Active listening and text such as The term active listening, coined in ..., not What is active listening?.
A neutral cross-reference is permissible – e.g., – but is usually better recast as a sentence with a link – )Bulverism, also known as the psychogenetic fallacy, is a related logic flaw.
A subset term identifies a set of members of a larger class. Common subset terms are including, among, and etc. Avoid redundant subset terms (e.g., mis-constructions like or The elements in stars include hydrogen, helium, etc.). The word including does not introduce a complete list; instead, use consisting of, or composed of.Among the most well-known members of the fraternity are included two members of the Onassis family
When there is a discrepancy between the term most commonly used by reliable sources for a person or group and the term that person or group uses for themselves, use the term that is most commonly used by recent[f] reliable sources. If it is unclear which is most used, use the term that the person or group uses.
Disputes over how to refer to a person or group are addressed by Wikipedia content policies, such as those on verifiability, and neutral point of view (and article titles when the term appears in the title of an article).
Use specific terminology. For example, it is often more appropriate for people or things from Ethiopia (a country in Africa) to be described as Ethiopian, not carelessly (with the risk of stereotyping) as African.
Loanwords and borrowed phrases that have common usage in English – Gestapo, samurai, vice versa – do not require italics. A rule of thumb is to not italicize words that appear unitalicized in general-purpose English-language dictionaries.
Names not originally written in one of the Latin-script alphabets (written for example in Greek, Cyrillic, or Chinese scripts) must be given a romanized form for use in English. Use a systematically transliterated or otherwise romanized name (Aleksandr Tymoczko, Wang Yanhong); but if there is a common English form of the name (Tchaikovsky, Chiang Kai-shek), use that form instead.
The use of diacritics (such as accent marks) for 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 . Provide redirects from alternative forms that use or exclude diacritics.
Spell a name consistently in the title and the text of an article. See relevant policy at Wikipedia:Article titles; see also Wikipedia:Naming conventions (use English). For foreign names, phrases, and words generally, adopt the spellings most commonly used in English-language references for the article, unless those spellings are idiosyncratic or obsolete. If a foreign term does not appear in the article's references, adopt the spelling most commonly used in other verifiable reliable sources (for example ). For punctuation of compounded forms, see relevant guidelines in § Punctuation.
Sometimes the usage will be influenced by other guidelines, such as § National varieties of English, which may lead to different choices in different articles.
Places should generally be referred to consistently by the same name as in the title of their article [f] name in round brackets (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 provide such a variant too often than too rarely. If more than one historical name is applicable for a given context, the other names should be added after the modern English name, that is: "historical name (modern name, other historical names)".. Exceptions are made if there is a widely accepted historical English name appropriate to the given context. In cases where such a historical name is used, it should be followed by the modern
Other media files include video and audio files. Style recommendations for such files largely follow recommendations for image files (as far as applicable).
Textual information should almost always be entered as text rather than as an image. True text can be colored and adjusted with CSS tags and templates, but text in images cannot be. Images are not searchable, are slower to download, and are unlikely to be read as text by devices for the visually impaired. Any important textual information in an image should also appear in the image's alt text, caption, or other nearby text.
For entering textual information as audio, see Wikipedia:WikiProject Spoken Wikipedia.
Photographs and other graphics should have captions, unless they are unambiguous depictions of the subject of the article or when they are "self-captioning" images (such as reproductions of album or book covers). In a biography article no caption is necessary for a portrait of the subject pictured alone, but one might be used to give the year, the subject's age, or other circumstances of the portrait along with the name of the subject.
Make links only where they are relevant and helpful in the context: Excessive use of hyperlinks can be distracting and may slow the reader down. Redundant links (like the one in the tallest people on Earth) clutter the page and make future maintenance harder. High-value links that are worth pursuing should stand out clearly.
Linking to sections: A hash sign (
#) followed by the appropriate heading will lead to a relevant part of a page. For example,
[[Apostrophe#Use in non-English names]] links to a particular section of the article Apostrophe.
Initial capitalization: Wikipedia's MediaWiki software does not require that wikilinks begin with an upper-case character. Capitalize the first letter only 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 .
Check links: Ensure the destination is the intended one; many dictionary words lead to disambiguation pages and not to complete or well-chosen articles.
Add external links with discretion; Wikipedia is not a link repository.
Other things being equal, keep markup simple. This makes wikitext easier to understand and edit, and the results seen by the reader more predictable. Use HTML and CSS markup sparingly.
An HTML character entity is sometimes better than the equivalent Unicode character, which may be difficult to identify in edit mode; for example,
Α is explicit whereas
Α (the upper-case form of Greek
α) may be misidentified as the Latin
Modifications in font size, blank space, and color style sheet and should be reserved for special cases only.are an issue for the Wikipedia site-wide
Specify font sizes relatively (for example with
font-size: 85%) rather than absolutely (like
font-size: 8pt). The resulting font size of any text should not drop below 85% of the page's default font size.
Do not use color alone to mark differences in text: they may be invisible to people with color blindness and useless in black-and-white printouts or displays.
Choose colors that are distinguishable by readers with the most common form of colorblindness, such as maroon and teal, and additionally mark the differences with change of font or some other means (maroon and alternative font face, teal). Avoid low contrast between text and background colors. Viewing the page with can help with the choice of colors. See also color coding.
Even for readers with unimpaired color vision, excessive background shading of table entries impedes readability and recognition of Wikilinks. Background color should be used only as a supplementary visual cue and should be subtle (consider using lighter, less-dominant pastel hues) rather than glaring.
: (description list markup) for simple visual indentation in articles (common as it may be on talk pages). It causes accessibility problems and outputs invalid HTML.
It is sometimes desirable to force a text segment to appear entirely on a single line—that is, to prevent a line break (line wrap) from occurring anywhere within it.
It is desirable to prevent line breaks where breaking across lines might be confusing or awkward. For example:
Scrolling lists, and collapsible templates that toggle text display between hide and show, can interfere with readers' ability to access our content. Such mechanisms are not to be used to conceal "spoiler" information. Templates are not normally used to store article text at all, as it interferes with editors' ability to find and edit it.
When such features are used, take care that the content will still be , and to the 45% (and climbing) of Wikipedia readers who use the mobile version of the site,[o] which has a limited set of features. Mobile ability to access the content in question is easy to test with the "Mobile view" link at the bottom of each page.[p]
This includes reference lists, tables and lists of article content, image galleries, and image captions. In particular, while some templates support a
collapsible parameter or manually-added CSS class, and this is permissible, the
autocollapse states should not be used in articles to pre-emptively force the closure of these elements, except as noted below. Any information hidden in this way when the page loads will be irreversibly invisible to the aforementioned classes of users, as well as a growing number of low-bandwidth users in Asia who reach a Wikipedia article via Google.[q] Several other CSS classes, used manually or by templates, will render content inaccessible to mobile users.[r]
Collapsed or auto-collapsing cells or sections may be used with tables if it simply repeats information covered in the main text (or is purely supplementary, e.g. several past years of statistics in collapsed tables for comparison with a table of uncollapsed current stats). Auto-collapsing is often a feature of navboxes. A few infoboxes also use pre-collapsed sections for infrequently accessed details. If information in a list, infobox, or other non-navigational content seems extraneous or trivial enough to inspire pre-collapsing it, consider raising a discussion on the article (or template) talk page about whether it should be included at all. If the information is important and the concern is article density or length, consider dividing the article into more sections, integrating unnecessarily list-formatted information into the article prose, or splitting the article.
Editors use "invisible" comments – not shown in the rendered page seen by readers of the article, but visible in the wiki source when an editor opens the article for editing – to communicate with one another.
Invisible comments are useful for alerting other editors to issues such as common mistakes that regularly occur in the article, a section title's being the target of an incoming link, or pointing to a discussion that established a consensus relating to the article. They should not be used to instruct other editors not to perform certain edits, although where existing local consensus is against making such an edit, they may usefully draw the editor's attention to that. Avoid adding too many invisible comments because they can clutter the wiki source for other editors. Check that your invisible comment does not change the formatting, for example by introducing unwanted white space in the rendered page.
To leave an invisible comment, enclose the text you intend to be read only by editors between
-->. For example:
This notation can be inserted with a single click in wiki markup, just under the edit pane in edit mode.
Wikipedians are encouraged to familiarize themselves with modern editions of other guides to style and usage, which may cover details not included here. Those that have most influenced the Wikipedia Manual of Style are: