shapefile

Shapefile is a popular geospatial vector data format used by geographic information systems (GIS). It was developed by Esri in the 1990s as an interchange format to facilitate data sharing among different GIS software. A shapefile is not a single file; it consists of at least three mandatory files that share the same base name: .shp, which stores the geometry of features; .shx, which contains the shape index; and .dbf, a dBase table that holds attribute data for each feature. Optional files include .prj, which defines the coordinate reference system, and .cpg, which specifies character encoding for attribute data.

The geometry stored in a shapefile is vector data representing points, lines (arcs), and polygons, including multipart shapes. Each feature has associated non-spatial attributes in the accompanying DBF table. Shapefiles support common geometry types and simple attribute schemas, but do not store topology or advanced data types.

Limitations include the use of the dBase format for attributes with a field name length limit and a lack of built-in topology or relational integrity. The format is not an open standard, but it has become a widely supported interchange format in GIS.

Today, shapefiles remain widely used for data exchange and quick mapping tasks. They are supported by virtually all major GIS software packages, though newer formats such as GeoPackage or GeoJSON are increasingly used for new projects.