U2014

The em dash, identified by the Unicode code point U+2014, is a punctuation mark used to indicate a strong break in a sentence or to set off parenthetical material, as an alternative to parentheses or commas, or to show interruption in dialogue. It derives its name from its width, which historically equals the em, or the width of the letter M in the current type size.

In typography, the em dash is longer than the en dash (U+2013) and the hyphen (U+002D). Its length is typically the full width of the type area (an em), making it visually distinct from other dash marks. In digital text, the em dash is represented as U+2014; in UTF-8 it appears as the byte sequence E2 80 94. HTML users can insert it with the named entity — or the numeric references — or —. In TeX and LaTeX, it is produced by three hyphens (---), while two hyphens (--) produce an en dash.

Usage varies by language and style guide. In English, em dashes are used to create abrupt breaks or to emphasize added information; spacing around the dash can differ—some style guides prefer spaces on both sides, others prefer no spaces. It can also substitute for parentheses or a colon in certain typographic styles.

History and variants: the em dash has its origins in traditional metal-type typography and became a standard punctuation mark in modern typesetting. Related marks include the en dash (U+2013) and the hyphen (U+002D).