| oxl | LITESTAR 4D Data File |
| oxml | OXML 2.0 Data |
| oxp | OmniRush eXtended Package |
| oyx | Lotus Approach Alternate Database Index |
| oz | Opera Job Management Compressed File |
| ozd | OZ Report Data |
| p00 | Commodore 64 Program Image |
| p01 | MicroStation Modification Project Resource File |
| p02 | MicroStation Modification Project Resource File |
| p03 | MicroStation Modification Project Resource File |
| p04 | MicroStation Modification Project Resource File |
| p05 | MicroStation Modification Project Resource File |
| p06 | MicroStation Modification Project Resource File |
| p07 | MicroStation Modification Project Resource File |
| p08 | MicroStation Modification Project Resource File |
| p09 | MicroStation Modification Project Resource File |
| p10 | MicroStation Modification Project Resource File |
| p12 | PKCS #12 Data File |
| p1d | PLUS+1 GUIDE Data |
| p21 | Express STEP Data Model |
| p2a | IBM Voice Type Languages Vocables Data |
| p2b | PeerGuardian 2 List |
| p2c | IBM Voice Type Languages Newuser Data |
| p2d | Move3D Data |
| p2f | WAMIT Poten to Force Data |
| p2m | PhotoWorks Appearance File |
| p2s | PCSX2 Saved State |
| p2z | Poser Compressed Pose Data |
| p3 | Primavera Project Planner Data |
| p3c | Primavera Project Planner Compressed Backup |
| p3t | Sony PlayStation 3 Theme |
| p4 | Perforce P4 Data |
| p4thor | Thor Exported Packet Records Data |
| p5m | PyMOL P5M Script |
| p7a | PKCS #7 Attached Signature |