Which file is necessary for the geometry of a shapefile?

The file necessary for the geometry of a shapefile is the .shp file. This file contains the geometric data, which defines the shapes of the features represented in the shapefile, such as points, lines, and polygons. Without the .shp file, the basic geometric structure that defines the spatial components of the geographic data would be missing.

The other files associated with a shapefile serve different purposes. The .shx file is an index file that allows for quick access to the geometries contained in the .shp file, but it does not contain any geometrical information itself. The .dbf file stores attribute data in a tabular format, providing additional information about the shapes, such as names or categories, but again, it does not include the geometry. The .prj file defines the coordinate system and projection information for the shapefile, which is crucial for correctly interpreting the spatial data, but it is not directly related to the geometry of the shapes.

Therefore, the .shp file is fundamental for representing the actual geometrical shapes in a shapefile dataset.