A dash is a punctuation mark that is similar to a hyphen or minus sign, but differs from both of these symbols primarily in length and function. The most common versions of the dash are the en dash (–) and the em dash (—), named for the length of a typeface's lower-case n and upper-case M respectively.
Usage varies both within English and in other languages, but the usual convention in printed English text is:
Either version may be used to denote a break in a sentence or to set off parenthetical statements – ideally with intradocument consistency. Style and usage guides vary, but often in this function en dashes are used with spaces and em dashes are used without them:
[Em dash:] A flock of sparrows—some of them juveniles—alighted and sang. [En dash:] A flock of sparrows – some of them juveniles – alighted and sang.
The en dash (but not the em dash) is also used to indicate spans or differentiation, where it may be considered to replace "and" or "to" (but not "to" in the phrase "from … to …"):
The French and Indian War (1754–1763) was fought in western Pennsylvania and along the present US–Canadian border (Edwards, pp. 81–101).
Caroline Lavinia Scott was born in Oxford, Ohio, the second daughter of John Witherspoon Scott, a Presbyterian minister and professor of science and mathematics at Miami University, and his wife Mary Potts Neal. Caroline had two sisters and two brothers. Although the family was not well off, her father ensured that his daughters as well as his sons were well educated. Wherever they lived, he filled the house with books, art, and music. Religion, was important in his and the family's life.
... Ah and SF9’s Rowoon! An adaptation of a popular web novel, “She Would Never Know” will tell the love story of the perfectionist Yoon Song Ah (Won Jin Ah) and her dashing younger colleague Chae Hyun Seung (Rowoon), who works with her on the marketing team for a cosmetics brand....