| pku | FidoNet Batched Newsgroup Data |
| pkw | CabnetWare Package |
| pky | PockeTTY Security Certificate |
| pl | TeX Property List |
| pl3 | Harvard Graphics ChartXL Palette Data |
| pl3 | Pathloss Link Design Data |
| pl4 | Micrografx Designer 4.0 Palette |
| pl4 | Pathloss Link Design Data |
| pl5 | Pathloss Link Design Data |
| pl9 | PCAnywhere Session Log |
| plan | Chief Architect Plan Data |
| plb | Insight II Pseudoatom Library |
| plb | MicroSim PCBoard Package Library |
| plb | Microsoft Robotics Developer Studio Playback Data |
| plb | PhotoLine Browser Index Data |
| ple | Messenger Plus! Live Encrypted Log |
| plf | PatchLink Developers Kit Exported Patch |
| plg | BPM Studio Playlist Group |
| plg | Microsoft Developer Studio Build Log |
| plgx | KeePass v2 Plugin |
| plib | SAM Old Dirichlet Mixture Prior Library |
| plj | Plus 2D Job Data |
| plk | COREX Part-of-speech Tag Data |
| plk | Password Safe Lock File |
| plma | Protomata-Learner PLMA Data |
| plmn | GSM Public Land Mobile Network Data |
| plmx | PDXpert PLM XML Data |
| plmxml | Siemens PLM XML Data |
| plo | Radio Toolbox Playlist |
| plot | Matplotlib Plot |
