| pkproj | Visual CCScript Project |
| pks | Oracle Package Specification |
| pl | Perl Script |
| pl | SWI-Prolog Source Code |
| pl1 | PL/I Source Code |
| plac | Plac Script |
| playground | Xcode Playground File |
| plb | Oracle PL/SQL Binary |
| plc | PL/B Source Code |
| pld | Oracle PLD Library |
| plg | µVision Protocol Data |
| pli | PL/I Source Code |
| pll | Oracle PLL Library |
| plog | PVS-Studio XML Analyzer Report |
| pltsuite | Safari Page Load Test Suite |
| plx | Oracle PLX Library |
| pm | Perl Module |
| pmq | Microsoft Target Analyzer File |
| pnw | PNW Source Code |
| po | GNU Gettext Portable Object |
| pod | Perl POD Document |
| podspec | CocoaPods Library Specification Data |
| policy | Java Policy Implementation Data |
| pom | Apache Maven Build |
| pou | PLCEdit Program Organization Unit |
| pp | Pascal/Delphi Source Code |
| pp | FreePascal Source Code |
| pp1 | FreePascal GO321v1 Compiled Unit |
| ppl | FreePascal Shared Library |
| ppo | Clipper Pre-processed Output File |
| ppu | FreePascal Compiled Unit |
| pql | VisualPQL Source Code |
| pr2 | dBASE IV Printer Driver |
| prc | Visual Studio .NET DB Project Stored Procedure |
| prd | RISCWatch Processor Resource Definition |