| 11. | .nc | Graphics (Unidata netCDF) ◊ Instructions for NC (Numerical Control) machine (CAMS) ◊ Preprosessed GOC source code file (non-error-checking version) (Geoworks) |
| 12. | .ncb | Class browsing information (Microsoft Developer Studio) |
| 13. | .ncc | CNC (Computer Numeric Control) control file (CamView 3D) |
| 14. | .ncd | Directory tree data (Norton Change Directory) |
| 15. | .ncf | Command File (Netware) ◊ Internal clipboard (Lotus Notes) |
| 16. | .nch | Newsgroup (Internet Explorer, Microsoft Outlook) |
| 17. | .ncm | Configuration message (Nokia Communicator) |
| 18. | .ncs | Netscape Conference Call file (Netscape) |
| 19. | .ncsa | Bitmap graphics (Hierarchical Data File) (NCSA) |
| 20. | .ndb | Network database (Intellicom - Compex) |