punctuation [Lat.,=point], the use of special signs in writing to clarify how words are used; the term also refers to the signs themselves. In every language, besides the sounds of the words that are strung together there are other features, such as tone, accent, and pauses, that are equally significant (see grammar and phonetics). In English, stress, pausing, and tonal changes interlock in a set of patterns often called intonations. Such features are represented by punctuation, indicated by signs inserted usually between words, and often following the feature they mark.
The intonations of declaration are classified in three types, symbolized by the comma (,), used to separate words or phrases for clarity; the semicolon (;), used to mark separation between elements in a series of related phrases, generally in a long sentence; and the full stop, or period (.), used to mark the end of a sentence. Other intonations are shown by the exclamation point (!); the interrogation point, or question mark (?); the parenthesis [( )], used to set off a word or phrase from a sentence that is complete without it; and the colon (:), typically used to introduce material that elaborates on what has already been said. Quotation marks ( " " ) indicate direct quotation or some borrowing, and usually demand special intonation. The ellipsis (…) is used to indicate the place in a passage where material has been omitted or a thought has trailed off. The long dash (—) is especially used in handwriting for incomplete intonation patterns.
Punctuation of material intended to be read silently rather than aloud—the far more usual case today—has introduced refinements designed to help the reader: brackets ([ ]), a secondary parenthesis; capital letters; paragraphing; and indentation. Two other frequent signs are the apostrophe ('), marking an omission of one or two letters, or a possessive case, and the hyphen (-), marking a line division or an intimate joining, as in compound words. These last two are practically extra letters, and their use, belonging with spelling rather than with punctuation, is highly arbitrary.
Each written language has its tradition of punctuation, often very different from that used in English; thus, in German nouns are capitalized, and in Spanish the beginnings of exclamations and of questions are marked with inverted signs. See also accent.
See W. D. Drake, The Way to Punctuate (1971); Words into Type (3d ed. 1974); D. Hacker, A Writer's Reference (4th ed. 1999); Univ. of Chicago Press, The Chicago Manual of Style (15th ed. 2003).