Understräck

Understräck is a Swedish term with two closely related meanings: the typographic practice of drawing a line beneath text to emphasize it, and the underscore character (_) used in computing and digital contexts.

Etymology and terminology: The compound derives from under (below) and sträck (line). In Swedish typography the act is usually called understrykning, while the symbol itself is commonly referred to as understräck in technical or informal writing. In computing contexts it is also described simply as the underscore.

History and characteristics: Underlining has medieval and early modern roots as a method to emphasize text when italics or boldface were unavailable. With typewriters and, later, digital text, the underscore character emerged as a printable symbol for use in identifiers, filenames, domain names and program source code. In Unicode the underscore is U+005F, and in ASCII it has the value 95.

Modern usage: In typography, underlining is less preferred for emphasis in professional typography, where italics or bold are used. For the web and digital naming, underscores are common in filenames and identifiers, though hyphens are often recommended for readability in URLs and documentation. In programming, underscores are widely used to separate words in identifiers (snake_case) in languages such as Python, while other languages use similar conventions. In Swedish contexts, the term understräck is primarily a technical or computing label, whereas understrykning remains the conventional term for the typographic practice.