What Is the Difference Between an Underline & an Underscore?

By James Red

Underlines usually signify HTML links. Underscores are something else.
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While some definitions list an underscore and an underline as the same thing, they are usually regarded as separate characters or tools used in writing and word processing.


An underline is a horizontal line that goes under a word or character This is an example of an underline. Underlines are usually used in HTML to signify hyperlinks. MLA style guidelines state that underlines must be used to identify books and other reference material. Underlines are also used stylistically to add emphasis.


An underscore ( _ ) is a type character that has its origins on typewriters. Today, it is primarily used as an alternative to a space marker when a space is not allowed due to program limitations. For example, if someone wanted to include a space on an email address but actual spaces were not allowed they would type "John_Smith."


Underlines can be created in HTML by using placing a before the text you want underlined and a at the end of the text. Most word processing programs, such as Microsoft Word and OpenOffice, allow you to underline by pressing "CRTL"+"U" on your keyboard. The underscore is accessed by holding shift on your keyboard and pressing the hyphen key, which is usually located to the right of the "0" key.