ligne

Ligne is a French noun meaning line, row, or queue, and it is used in a variety of contexts from geometry to transportation to typography. The word derives from Old French ligne, from Latin linea meaning thread or line.

In geometry, a line is a straight, one-dimensional figure that extends without end in both directions. It has length but no width. In Cartesian coordinates, a line can be described by a linear equation, such as ax+by=c, or by the slope-intercept form y=mx+b. A line is determined by two distinct points; the segment joining them is a line segment.

As a graphic element, a line is a mark that connects two points and can vary in direction, length, and thickness. In typography and publishing, ligne can refer to a line of text; in broader usage, lines structure writing and drawing, and lines of poetry or music are described as lines as well.

In transportation, ligne denotes a route or service, such as a railway line (ligne de chemin de fer) or a metro line (ligne de métro). Lines are typically identified by numbers or names to distinguish different routes within a network.

In computing and data handling, a line can mean a line of text in a file, and the term ligne de commande refers to the command line used by a shell or terminal.

See also: Line (geometry), Line (text), Public transport line, Command line.