About SHP Files

The SHP format, also known as "shape format" or "shapefile," is published by ESRI and is widely used for data interchange in GIS. Shapefiles store both geometry and attribute data for features. A single shapefile consists of three physical files with the same file name, but different file extensions:

• .shp—Points, polylines, and polygon geometric data can be stored in a shp file. However a single shp file can contain only one type of geometry.
• .shx—Index to the geometric map features
• .dbf—Table data associated with the map features.

There may also be a .prj file, which defines the coordinate system for the shapefile.