| PL | PERL Script |
| PL | Prolog Source Code |
| PL | Harvard Palette |
| PL | TeX Font Metrics |
| PL1 | 3D Home Architect Floor Plan |
| PL3 | Harvard Graphics DOS 3.0 Chart Palette |
| PL4 | Micrografx Designer Palette |
| PLB | FoxPro Runtime API Library for DOS |
| PLB | LogoShow Screensaver |
| PLC | Lotus Add-in |
| PLD | PLD2 Source File |
| PLG | Microsoft HTML Form |
| PLI | Oracle 7 Data Description |
| PLL | Prelinked Library |
| PLM | DisorderTracker2 Module |
| PLN | WordPerfect Spreadsheet |
| PLR | Descent Pilot File |
| PLS | DisorderTracker2 Sample |
| PLS | WinAmp MPEG PlayList File |
| PLS | Shoutcast File |
| PLS | MYOB Data File |
| PLT | AutoCAD HPGL Vector Graphic Plotter File |
| PLT | Gerber Sign-making Software File |
| PLT | Bentley's CAD MicroStation Driver Configuration for Plotting |
| PLY | Harvard Spotlight Presentation |
| PLY | Autodesk Animator Polygon Format |
| PM | PageMaker Document |
| PM | Bitmap Picture |
| PM | Perl Module |
| PM3 | Aldus PageMaker 3 Document |
| PM4 | Adobe PageMaker 4 Document |
| PM5 | Pagemaker 5.0 Document |
| PM6 | Pagemaker 6.0 Document |
| PMA | Windows NT Performance Monitor Alert |
| PMC | Windows NT Performance Monitor Chart |
| PMC | A4Tech Scanner Image |
| PMD | Pagemaker File |
| PMG | Pagemaker Group File |
| PMI | Pegasus Mail Message Folder Index File |
| PML | Windows NT Performance Monitor Log File |
| PML | PADGen Program Information |
| PML | Pegasus Mail Distribution List |
| PMM | Pegasus Mail Mail Message Folder |
| PMO | Print Master Gold Text |
| PMP | VideoCraft GIF Animator Project |
| PMR | Windows NT Performance Monitor Report |
| PMW | Windows NT Performance Monitor Workspace |
| PN3 | Harvard Printer Driver |
| PNG | Portable Network Graphics Graphic |
| PNG | Paint Shop Pro Browser Catalogue |
| PNM | UNIX "Portable Any Map" Image |
| PNT | MacPaint Graphic File |
| POG | Descent 2 File |
| POL | Policy File (various) |
| POL | InnovMetric Binary |
| POL | Music File |
| POP | Pop-Mail Message |
| POP | dBase Popup Menu |
| POS | ProCite Output Styles |
| POS | QuickPOS IIF File |
| POT | Microsoft PowerPoint Template |
| POV | Persistence of Vision Ray-Tracer |
| POW | Power-Chords Chord Chart |
| PP | Amiga Power-Packer Compressed Archive File |
| PP4 | Picture Publisher 4 Bitmap |
| PP5 | Picture Publisher 5 Bitmap |
| PPA | PowerPoint Add-in |
| PPB | WordPerfect Print Preview Button Bar |
| PPD | PostScript Printer Description |
| PPF | Jasc Paint Shop Pro 7 Preset File |
| PPF | Turtle Beach Pinnacle Program File |
| PPG | MS PowerPoint Presentation |
| PPI | MS PowerPoint Graphics File |
| PPJ | MS PowerPoint Graphics File |
| PPJ | Adobe Premiere Video Editing File |
| PPL | Harvard Polaroid Palette Plus ColorKey Driver |
| PPM | Portable Pixelmap Bitmap |
| PPO | Clipper Preprocessor Output |
| PPP | Serif PagePlus Desktop Publishing Publication |
| PPP | Parson Power Publisher |
| PPS | Microsoft PowerPoint Slide Show |
| PPS | Paint Shop Pro Image |
| PPT | Microsoft PowerPoint Presentation |
| PPT | Page-Plus Template |
| PPV | Microsoft Pocket Powerpoint Presentation for Windows CE |
| PPX | Serif PagePlus Publication |
| PPZ | PowerPoint Packaged Presentation |
| PQ | Adobe Pagemaker Default Printer Style |
| PQA | Palm Query Application File |
| PQF | Corel Presentations Runtime |
| PQI | Power Quest Drive Imaging Software |
| PQW | Corel Presentations Runtime |
| PQX | Power Quest DRive Image Index |