If a Title value has not been set for a Frame, then a suitable default is supplied.
The default supplied by the Frame class is "<n>-d co-ordinate system", where <n> is the number of Frame axes (Naxes attribute).
Specialised Frames (SkyFrame, SpecFrame, etc.) re-define the default Title value to be appropriate to the particular co-ordinate system being represented.
KAPPA --- Kernel Application Package