LineString

LineString is a basic geometry type used in geographic information systems to represent linear features. It consists of an ordered sequence of points, and the line is formed by connecting each consecutive pair of points with straight segments. A LineString contains two or more points and is typically two-dimensional, though it may include a third coordinate for elevation. The geometry is not implicitly closed; if the first and last points coincide, the object may be treated as a LinearRing in polygonal contexts.

LineStrings exist in various coordinate reference systems and dimension options. They can be defined in two dimensions (x, y) or in three dimensions (x, y, z). The length of a LineString is the sum of the distances between successive points. In geographic coordinates, length may be computed geodetically using the curvature of the earth; in projected coordinate systems, planar distance is common.

LineStrings are encoded in formats such as WKT and GeoJSON. In WKT, a Linestring is written as LINESTRING (x1 y1, x2 y2, ...). In GeoJSON, a LineString is an object with type "LineString" and coordinates as an array of positions, e.g., [[x1, y1], [x2, y2], ...] (optionally including z).

LineStrings are one-dimensional geometries used to represent features like roads, rivers, and utility lines. They have no area but can participate in spatial analyses (length, intersection, buffering) and can be combined into collections such as MultiLineString or used within network datasets.