A5 is a global geospatial index. It is the pentagonal equivalent of other DGGSs, like S2 or H3, but with higher accuracy and lower distortion.
A5 is used for representing points, lines, and polygons in a unified cell format, which is well suited for combining datasets and aggregating data.
Data from all around the world can be directly compared due to the practically equal areas of all A5 cells.