The Common Data Format (CDF) is a conceptual data abstraction for storing,
manipulating, and accessing multidimensional datasets. The basic component of
CDF is a software programming interface that is a device- independent view of
the CDF data model. The application developer is insulated from the actual
physical file format for reasons of conceptual simplicity, device independence,
and future expandability. CDF files created on any given platform can be
transported to any other platform onto which CDF is ported and used with any
CDF tools or layered applications.

The CDF software, documentation, and user support services are provided by NASA
and available to the public free of charge. There are no license agreements or
costs involved in obtaining or using CDF.

A comparison between CDF, netCDF, HDF and HDF5 is available at
https://cdf.gsfc.nasa.gov/html/FAQ.html
