Boldface (text like this) is common in Wikipedia articles, but only for certain usages.

Article title terms

The most common use of boldface is to highlight the article title, and often synonyms, in the lead section (first paragraph). This is done for the majority of articles, but there are exceptions. See Lead section – Format of the first sentence for in-depth coverage.

Other uses

Use boldface in the remainder of the article only in a few special cases:

• Table headers and captions
• Definition lists (example: Glossary of trucking industry terms in the United States)
• Volume numbers of journal articles, in some bibliographic formats

In the first two cases, the appropriate markup automatically adds the boldface formatting; do not use the explicit triple-apostrophe markup. Similarly, in the third case, the formatting should generally be added implicitly by use of a template, such as {{citation}}.

Contraindications

Use italics, not boldface, for emphasis in article text.

It is technically possible to bold Greek and Cyrillic alphabets, but this should be avoided.

Wikipedia automatically puts headings (section titles) in boldface. Bolded headings, though technically possible, will appear especially bold, and are not appropriate.

Italic type (text like this) has several uses on Wikipedia.

• Certain scientific names
  • Genera and all lower taxa (but not higher taxa)
  • Genes (but not proteins encoded by genes)
• Court cases
• Named vehicles
  • Trains and locomotives
  • Ships
  • Ship classes
• Works of art and artifice
  • Art exhibitions
  • Books
  • Cantatas and motets
  • Comic strips and webcomics
  • Computer and video games (but not other software)
  • Films (including short films) and documentaries
  • Long or epic poems
  • Multi-episode television shows (i.e., serials)
  • Musical albums
  • Musicals
  • Operas, operettas, oratorios
  • Orchestral works
  • Paintings, sculptures and other works of visual art
  • Periodicals (newspapers, journals, and magazines)
  • Plays
  • Television series and serials

Abbreviations of the above should also be italicized.

Website titles may or may not be italicized depending on the type of site and what kind of content it features. Online magazines, newspapers, and news sites with original content should generally be italicized (such as Salon.com or The Huffington Post). Online encyclopedias and dictionaries (like Wikipedia or Urban Dictionary) should also be italicized. Other types of websites should be decided on a case-by-case basis.

Emphasis

The use of italics for emphasis on Wikipedia should follow good English print style. Italics may be used to draw attention to an important word or phrase within a sentence when the point or thrust of the sentence may otherwise not be apparent to readers, or to stress a contrast:

Gellner accepts that knowledge must be knowledge of something; and that some philosophical theories may arise from linguistic confusion.

It may be preferable to avoid the need for italics by rewriting a sentence more explicitly.

Italics may also be used where, in the course of using a term in an article, that term is being defined, introduced or distinguished in meaning. For instance, in the consciousness article:

Access consciousness is the phenomenon whereby information in our minds is accessible for verbal report and reasoning.

If, however, a term is strictly synonymous with the subject of the article, then bold face should be used in place of italics. The first occurrence of a technical term may be both linked and italicised if the term also has its own article (or section) corresponding exactly to the meaning when used in the present article. A term being introduced is often mentioned as a word (see below) rather than playing its normal grammatical role; if so, it should be italicised or quoted, but not both.

Words as words

Use italics when writing about words as words, or letters as letters (to indicate the use–mention distinction). This category may also use quotation marks to distinguish words as words. For example:

• Deuce means "two".
• The term panning is derived from panorama, which was coined in 1787.
• The most common letter in English is e.

Foreign terms

Wikipedia prefers italics for phrases in other languages and for isolated foreign words that do not yet have everyday use in non-specialised English. Use the native spellings if they use the Latin alphabet (with or without diacritics)—otherwise Anglicise their spelling. For example: "Gustav I of Sweden liked to breakfast on crisp bread (knäckebröd) open sandwiches with toppings such as messmör (butter made from goat's milk), ham (skinka), vegetables (grönsaker) like tomatoes (tomat) or cucumber (gurka)." In accordance with the guide to writing better Wikipedia articles, use foreign words sparingly.

Loanwords or phrases that have common use in English, however—praetor, Gestapo, samurai, esprit de corps, e.g., i.e.—do not require italicization. If looking for a good rule of thumb, do not italicize words that appear in Merriam-Webster Online.

If there is a reason to include native spelling in a non-Latin script, it can be placed in parentheses. Text in non-Latin scripts (such as Greek or Cyrillic) should not be italicized at all—even where this is technically feasible; the difference of script suffices to distinguish it on the page.

A proper name is usually not italicized when it is used, but it may be italicized when the name itself is being referred to (see Words as words).

Scientific names of organisms are formatted according to normal nomenclature, with genus and species (and subgenus and subspecies if applicable) in italics (see the main section). For example: "The largest carnivore in family Tyrannosauridae was T. rex itself" but "Unicorn was an album by the band T. Rex".

For better accessibility, Latin quotations should never be set in all caps or small caps, even when such use might seem anachronistic.

See also Template:Lang/doc for marking passages in a foreign language with {{lang|xx}} and {{lang-xx}}.

Quotations

It is normally incorrect to put quotations in italics. They should only be used if the material would otherwise call for italics, such as for emphasis or to indicate use of non-English words. Indicate whether italics were used in the original text or whether they were added later. For example:

Now cracks a noble heart. Good night sweet prince: And flights of angels sing thee to thy rest!

(emphasis added)

Variables

Program variables

Variables in computer programs and symbols for program variables within plain-English prose and in computer source code presented as textual content can be marked up with the <var> element, or its wikimarkup equivalent, the {{var}} template: