Underscore

"Underline" redirects here. For Linear park trail in Miami, see The Underline.

"Underscores" redirects here. For the American musician, see Underscores (musician).

For other uses, see Underscore (disambiguation).

_ ◌̲o
Underscore
In Unicode	U+005F _ LOW LINE (_, _) U+0332 ◌̲ COMBINING LOW LINE
Graphical variants
＿
U+FF3F ＿ FULLWIDTH LOW LINE
Different from
Different from	U+0331 ◌̱ COMBINING MACRON BELOW
Related
See also	U+2017 ‗ DOUBLE LOW LINE U+2381 ⎁ CONTINUOUS UNDERLINE SYMBOL U+2382 ⎂ DISCONTINUOUS UNDERLINE SYMBOL U+FE33 ︳ PRESENTATION FORM FOR VERTICAL LOW LINE

Underlining was developed for mechanical machines like this Underwood typewriter which had no bold or italic type. The only way to emphasize text that was typewritten was to back up the carriage and type underscores beneath the text. Underlining was a workaround for shortcomings in typewriter technology.

Underscored or underlined text.

An underscore or underline is a line drawn under a segment of text. In proofreading, underscoring is a convention that says "set this text in italic type", traditionally used on manuscript or typescript as an instruction to the printer. Its use to add emphasis in modern finished documents is generally avoided.

The (freestanding) underscore character, _, also called a low line, or low dash, originally appeared on the typewriter so that underscores could be typed. To produce an underscored word, the word was typed, the typewriter carriage was moved back to the beginning of the word, and the word was overtyped with the underscore character.

In modern usage, underscoring is achieved with a markup language, with the Unicode combining low line or as a standard facility of word processing software. The free-standing underscore character is used to indicate word boundaries in situations where spaces are not allowed, such as in computer filenames, email addresses, and in Internet URLs, for example Mr_John_Smith.