CDF is an acronym which refers to both the Common Data Format (as defined and maintained by NASA GSFC) and this Python package.
The CDF package contains three interfaces to deal with CDF formatted files. Two of these are simple mappings from existing interfaces in the NASA GSFC CDF libraries with Pythonization (for instance, throwing exceptions rather than returning error codes.) Their signatures and usage are mechanical mappings from their C counterparts.
The CDF package contains an additional interface, called the pythonic interface. The pythonic interface allows manipulation of the CDF formatted files in a manner more familiar and comfortable to Python programmers. Typical usage of the pythonic interface will require no knowledge of the details of CDF internal data types or APIs.