This post details the function of various symbols that appear the top of a line of type to communicate additional information about the text.
The apostrophe signals that, depending on usage, one or more letters are missing or are being added to perform a grammatical function. An apostrophe
• marks omission of one or more letters (as in the contraction of cannot to can’t or, in an extreme case, of the substitution of fo’c’stle for forecastle)
• marks possessive case (as in “John’s hat” or “the girls’ smiles”)
• marks plurals of individual characters, as in “dot the i’s and cross the t’s.”
The primary use of double quotation marks (called, in British English, inverted commas) is to indicate direct quotation of spoken or written content. (Single quotation marks are used only to frame quotations within quotations, as in this section of this post, or in technical usage such as in linguistics texts.)
A self-contained quotation is capitalized (“She asked, ‘Where are you going?’”) A partial quotation is not capitalized when it is syntactically integrated into the framing sentence (“He explained that they ‘had some issues to work out.’”) They also frame meanings and definitions (“That sign means ‘Stop’”; “The definition of insanity is ‘Doing the same thing over and over again and expecting different results’”).
Quotation marks are sometimes employed as scare quotes and sneer quotes, which emphasize ironic usage (“After the bombing, no one remained alive in the village to celebrate its ‘pacification’”) or signal that a writer is using but not endorsing a term (“Beware executives who want to ‘leverage’ everything”). They are unnecessary when naming something, even when the term is slang used for a meaning other than its original sense (“The process of extracting digital content is called ripping”).
Use of so-called preceding a term in scare quotes is redundant.
Avoid use of quotation marks to set off clichés (“This behavior creates lethal ‘blind spots’ in an organization”).
Quotations also set off titles of components of compositions when referred to elsewhere than in the composition itself, such as references to the following:
• newspaper or magazine articles
• titles of chapters in a book
• titles of short stories or short poems
• names of episodes of television series
• titles of songs
• titles of speeches
In addition, quotations frame a term consisting of more than one word when the term refers to itself rather than to the concept the term represents (“What does “net neutrality” mean?); italicize single words used as words (“The word strike can be used as a noun, a verb, or an adjective”).
Avoid using straight quotation marks (“), which have a plain, primitive appearance. (But see below.)
A prime is a symbol similar to an apostrophe or a close quotation mark that in technical usage follows a number to denote a unit; in lay content, a single prime (′) most frequently represents feet or minutes, and a double prime (″) indicates inches or seconds (“The deck is 10′ 6″ by 12′”) or minutes (“The duration was 3′ 36″”). (There are also triple and quadruple primes.) Primes are sometimes indicated by simple straight quotation marks (‘ and “).
These symbols (which originated as miniature Roman numerals I, II, and III) are best reserved for informal use or in practical content such as text about woodworking, or in charts or tables. Otherwise, spelling out the terms the primes represent is recommended.
An ordinal indicator is a superscripted, or raised, number, letter, or other character used in text as a cross-reference to a footnote or endnote or a list of referenced sources. These are employed, especially in academic texts, to direct readers to additional information that would be distracting if embedded in the running, or regular, text. When encountering an ordinal indicator, readers can ignore it or can direct their attention to the cross-referenced material and then return to the position of the indicator and resume reading the running text. Superscript characters are located directly after the pertinent word, phrase, or sentence in the text, though they follow, rather than precede, punctuation (with the exception of a dash, which the indicator should precede).
The degree symbol (°), following a number, most often represents degrees of arc or of temperature, though it has other specialized functions. Usually, the symbol is appropriate only for technical usage or for charts and tables and should be replaced by degrees in lay content.
An asterisk (*)—the word is from the Greek word for “little star”—has various functions in scientific disciplines, but in general writing, it is used as an ordinal indicator when, because of the small number of notes in a text, a sequential system of numbers or letters are not required. (However, sometimes, when there are a handful of references requiring such indicators but numbers or letters are not used, other symbols such as the dagger and double dagger are employed in a traditional hierarchy.) Asterisks also take the place of bullets, frame a word or phrase to represent italic or boldface type when it is not available, and appear in a group of three centered on a page to denote a major narrative transition.
A bullet is a typographic mark, usually a solid dot but often represented by other characters, used in a vertical list when numbers are not appropriate because the list is not hierarchical or sequential. (See this post and others at DailyWritingTips.com for more information about vertical lists.)
A ditto mark is a close quotation mark used to represent a repeated number, word, or phrase, as in an inventory list in which the quantity of one item is identical to that of another item. It is generally not used in formal writing; in informal usage, the word ditto is shorthand for “the same,” as in the declaration “I’m hungry,” and the response “Ditto,” indicating that the respondent is also hungry.
A dagger is a typographical mark resembling a knife pointing downward, or a Christian cross. The dagger, and the double dagger, often appearing more as a plus sign stacked atop another, are sometimes used to signal a footnote when an asterisk has already been employed. The daggers also have distinct uses in notation for various disciplines and pastimes.
The symbols ©, ®, ℠, and ™ denote specific rights to intellectually property, including compositions, brand names, and the like. They are employed in commercial communications to represent that the users are honoring the right of the copyright holder or trademark holder, for example, to claim the intellectual property, but they are not required when mentioning, for example a brand name. Publishers are required, however, to obtain permission to reproduce, for example, an excerpt from a song’s lyrics.