July 22nd 2010
A Shapefile is a commonly used binary format that stores geometric data such as lines, points and polygons along with attribute information that describes what that geometric data represents. Despite the term “shapefile,” a shapefile is actually a set of several files, three of which are mandatory to store the data comprising a “shapefile”. The first of these files is the .shp file, which stores the actual geometric data. Another file, the .shx file, is an index file that allows seeking forwards and backwards very quickly. The last mandatory file in a “shapefile” is the .dbf file, which stores the attribute information for the geometric data.