Here are the data structures with brief descriptions:
| Ccelprm | Celestial transformation parameters |
| Cdisprm | Distortion parameters |
| Cdpkey | Store for DPja and DQia keyvalues |
| Cfitskey | Keyword/value information |
| Cfitskeyid | Keyword indexing |
| Clinprm | Linear transformation parameters |
| Cprjprm | Projection parameters |
| Cpscard | Store for PSi_ma keyrecords |
| Cpvcard | Store for PVi_ma keyrecords |
| Cspcprm | Spectral transformation parameters |
| Cspxprm | Spectral variables and their derivatives |
| Ctabprm | Tabular transformation parameters |
| Cwcserr | Error message handling |
| Cwcsprm | Coordinate transformation parameters |
| Cwtbarr | Extraction of coordinate lookup tables from BINTABLE |