Introducing Geographic Information Systems with ArcGIS: A Workbook Approach to Learning GIS, 3rd Edition

Shapefiles—Layout in the Computer

The format for a shapefile on a disk drive is also much simpler than that of a coverage or a geodatabase. Basically, at least three files in a folder are required for a shapefile. If a folder named AMENITIES contains a shapefile named LAWN_SPRINKLERS, then AMENITIES will contain at least these files:

• lawn_sprinklers.shp (contains the geographic information)
• lawn_sprinklers.shx (contains the spatial index to the geographic information)
• lawn_sprinklers.dbf (contains the dBASE table for the attribute information)

Other files (lawn_sprinklers.sbx, lawn_sprinklers.sbn, lawn_sprinklers.prj (containing the projection information) and lawn_sprinklers.shp.xml (containing the metadata) may also be present. So the term “shapefile” is somewhat a misnomer, if one expects a single computer file. ArcCatalog, of course, represents as shapefile as a single entity, but to the operating system, it is several files. You could actually move a shapefile from one folder to another using the operating system. You would simply move all the constituent files, but this is not a recommended practice; use ArcCatalog instead. (Recall that with geodatabases there is no issue with moving or renaming because you can’t see the constituent feature classes with the operating system; they are locked away in a single database file.)

When you access a folder containing the files that make up a shapefile in ArcMap or ArcCatalog, you see only the designation—continuing our example—lawn_sprinklers.shp. ...