| mpsy | CodeWarrior Debugger Symbols Data |
| mps_ | MPW Shell Data |
| mpws | MathPiper Worksheet |
| mpx | Alpha Five Temporary Index |
| mpx | BasicX Compiler Map Data |
| mpx | Visual FoxPro Compiled Menu Program |
| mq4 | MetaQuotes Language 4 Source Code |
| mq5 | MetaQuotes Language 5 Source Code |
| mqh | MetaTrader MetaQuotes Language 4 Header |
| mql4 | MetaTrader MetaQuotes Language 4 File |
| mql5 | MetaTrader MetaQuotes Language 5 File |
| mqs | IBM MDWorkbench MQL Script |
| mqt | MetaTrader MetaQuotes Language 4 Template |
| mrlv | MCS Component Policy Editor Rollover Image Component |
| ms | Modula-3 Intermediate Assembly Code |
| msapp | Power Apps Studio Canvas Application |
| msb | Oracle Binary Message File |
| msct | MOPEKS Script File |
| msd | Xilinx ISE BitGen Mask Information |
| msdev | Visual Studio Makefile |
| msg | FoxPro FoxDoc Message |
| msg | Uniface Message Texts Data |
| msh | MaxL Shell Script |
| msh | Microsoft Shell Script |
| msha | Microsoft Help Asset File |
| mshc | Microsoft Help Container |
| mshi | Microsoft Help Index File |
| mshxml | Microsoft Shell Types File |
| msil | Microsoft Intermediate Language Data |
| msk | Xilinx ISE BitGen Mask Data |
| msl | MAINSAIL Source Code |
| msl | Mapping Specification Language Data |
| msl | ProWorx NXT MSL Loadable |
| msp | MaxScript Page |
| mspx | Microsoft Presentation Framework Page |
| mstx | Windows Template Studio Template Data |
| msvc | Visual Studio C++ Compiler Makefile |
| mthd | MOPEKS Method File |
| mthm | MCS Theme Policy Editor Theme Policy |
| mti | M-Tx Music-From-Text Translator Include |
| mtl | Amazon Lumberyard Material Data |
| mtn | Monotone Database |
| mtpf | Moony-TexturePacker Texture |
| mtra | MascotCapsule Resource Data |
| mtrl | Esenthel Engine Material Data |
| mtx | M-Tx Music-From-Text Source Code |
| mtx | Visual Studio Manual Test Data |
| mtxt | MOPEKS Text File |
| mu | MuPAD Source Code |
| muf | Alpha Five Concurrent Users Data |
| muf | ProtoMuck Multi User Forth Program |
| mui | Multilingual User Interface Data |
| mui | OpenGL GLUT Data |
| mun | Windows System Resource Archive |
| mv | Miva Script Source Code |
| mvc | Compiled Miva Script Program |
| mvq | mvQuery Query |
| mvt | Miva Merchant Module |
| mvx | Multimedia Fusion Movement Extension |
| mwc | Make Project Creator Input Data |
| mx | Modula-3 Linker Information |
| mx3 | MATLAB Windows Dynamically Linked Subroutines Data |
| mxe | Max Windows 32-bit External Object |
| mxe64 | Max Windows 64-bit External Object |
| mxl | MaxL Script |
| mxls | MaxL Encyrpted Script |
| mxml | Adobe Flex Markup Language |
| mxo | Max Macintosh External Object |
| myapp | Visual Studio Application XML |
| mz | Mezzo Source Code |
| mzb | MegaZeux Board Data |
| mzi | Mezzo Interface File |
| mzx | MegaZeux World |
| n | Neko Bytecode |
| nas | Nasal Script |
| nav | Xilinx ISE NGDBuild Navigation Data |
| nb0 | Windows CE Boot Loader Image |
| nbc | Next Byte Codes Source Code |
| nbin | Compiled NASL Script |
| nc | GEOS Preprocessed GOC Source Code |
| nc | neatComponents Data |
| ncb | Visual Studio No Compile Browse File |
| ncl | NCAR Command Language File |
| ndb | ProWorx NXT Short Comment with Blocking |
| ndf | ProWorx NXT Short Comment File |
| ndll | Neko Dynamic Library |
| ndx | IBM Rational XDE NDX Data |
| ndx | WinDev HyperFileSQL Index |
| ned | OMNeT++ Network Description |
| neff | Neuron Executable File Format Data |
| neko | Neko Source Code |
| nesl | NESL Source Code |
| net | Borland Database Engine Log |
| netmodule | Visual C Linker .NET Module |
| nfm | Delphi .NET Form |
| nfx | NetObjects Fusion Components |
| nga | Xilinx ISE NetGen Data |
| ngi | NGI Package |
| ngo | Norton Guide Linker Object |
| ngo | Xilinx ISE Logical Description Data |
| nhs | NHibernate Settings File |
| ni | NetObjects Fusion Preview |
| nib | Apple Interface Builder Resources |
| nim | Nim Source Code |
| nim | Nimrod Source Code |
| nimble | Nimble Package Data |
| nir | AdminStudio Repackaging Wizard Output |
| njk | Nunjucks Template |
| njp | njPipes Compiler Data |
| nk | NUKE Script |
| nkple | Nuke Personal Learning Edition Script |
| nky | Xilinx ISE BitGen Key Data |
| nlf | Xilinx ISE NetGen Log |
| nls | NetLogo Source Code |
| nmc | Xilinx ISE Physical Macro Library |
| nmf | Native Client Manifest File |
| nmk | NMake Makefile |
| nml | NML Language Source Code |
| nms | Numega SoftICE Loader Data |
| nod | NetObjects Fusion Site File |
| node | Node.js Binary Addon |
| nokogiri | Nokogiri Source Code |
| noq | NOQ Source Code |
| npi | dBase Application Generator Source Code |
| npmignore | NPM Ignore |
| nqc | Not Quite C Source Code |
| nqp | Visual Studio Code Data |
| nsb | NS Basic/CE Data |
| nse | Nmap Scripting Engine Script |
| nsh | NSIS Header |
| nsi | NSIS Script File |
| nsl | nsL Script |
| nupkg | NuGet Package |
| nuspec | NuGet Specification Data |
| nut | Squirrel Source Code |
| nvb | NVSG SDK Scene Graph |
| nvv | Nvidia Vertex Shader Profile |
| nw | NW.js App Package |
| nxb | C4 Engine Binary Model Data |
| nxc | Not eXactly C Source Code |
| nxd | AdaOS Debugging Information |
| nxe | AdaOS Main Program Module |
| nxg | eSite Builder NXG Web Page |
| nxp | AdaOS Profiling Information |
| nxs | AdaOS Support Module |
| nxu | C4 Engine XML Model Data |
| o | Compiled Object File |
| o1 | Free Pascal Object File for GO321v1 Platform |
| oat | Android Compiled OAT |
| ob2 | Oberon 2 Source Code |
| obak | WinSQL Offline Backup Data |
| obe | Objeck Executable File |
| obh | Hitachi Ladder Editor Object Program |
| obj | Intel Relocatable Object Module |
| obj | Visual Studio Compiled Object |
| obl | Objeck Compiled Library |
| obn | Oberon 2 Module Source Code |
| obr | Borland C++ Object Browser Data |
| obs | Objeck Source Code |
| obs | ObjectScript Script |
| obv | ObjectScript Form |
| obyx | Obyx Script |
| oc | Esterel Compiler Automaton Code |
| oca | Visual Basic Control TypeLib Cache |
| ocb | Origin Code Builder Object |
| occ | CC5X C Compiler Output File |
| ocl | Object Constraint Language File |
| octest | Xcode Objective-C Unit Test Bundle |
| ocz | Origin Encrypted C Source Code |
| odb | Psion OVAL Database |
| odcl | OpenDCL File |
| odd | TEI Source Code |
| odex | Android Optimized Dalvik Executable |
| odg | Psion OVAL Dialog File |
| odh | Visual Studio Interface Definition Language Data |
| odkbuild | ODK Build Form |
| odl | Object Description Language |
| odp | OPRO Direct to Print File |
| oem | Windows OEM Setup File |
| ofd | OPRO Form Data |
| ofp | Objecteering Project |
| ofr | Psion OVAL Form |
| ogd | Oracle Forms Graph |
| ogre | OGRE 3D Data |
| ohc | Delphi OpenHelp Contents |
| ohi | Delphi OpenHelp Index |
| ohl | Delphi OpenHelp Links |
| ohp | Delphi OpenHelp Data |
| ok | Qedit OK Data |
| oks | OKScript Script |
| olb | Oracle Forms Object Library Module Binary |
| olb | Synergy/DE Object Library |
| ole | Object Linking and Embedding Data |
| oln | Microsoft Visual C++ Outline Examples Data |
| olt | Oracle Forms Object Library Module Text |
| om | OMake Makefile |
| omc | OMake Cache File |
| omh | Omnis Studio Header |
| omk | Ocera Make System Script |
| oml | Outsystems Markup Language Data |
| omo | OMake Object File |
| oo | FreePascal Object |
| oog | PyGraph Object Oriented Graphics Data |
| oot | Python pytest-oot Test |
| op | Origin Preprocessed Data |
| opa | OPA Source Code |
| opa | Psion OPL Translated Application |
| opentag | OpenTag Document |
| opf | Obsidium Project File |
| opo | Psion OPL Object |
| oppo | Oppo Core |
| opr | OPRO Print Report |
| opt | Microsoft Visual Studio Workspace Options |
| opt | ProWorx NXT List Module Option File |
| opt | XFLOW Options Data |
| opt | µVision Project Options Data |
| orc | µVision Global Register Coloring Data |
| orderedtest | Visual Studio Ordered Test Data |
| original | Netobjects Fusion Components Bbscomp Message Data |
| ors | Psion OVAL Resource File |
| os | ObjectScript Source Code |
| osav | ANSYS Element Saved Old Data |
| osax | AppleScript Scripting Addition |
| osc | oBIX Source Code File |
| osd | Open Software Description File |
| osl | Open Shading Language Source |
| oso | Open Shading Compiled Object |
| otf | VAMPIR Open Trace Format Data |
| ovd | Borland ObjectVision Source |
| ovd | NetCOBOL PowerFORM Overlay Descriptor |
| ovg | ObjectVision Converted Graphic Data |
| ovp | Psion OVAL Project |
| ovx | Psion OVAL Control |
| ow | FreePascal 1.0.x Object |
| owl | OWL Source Code |
| owl | Web Ontology Language Document |
| ox | Ox Program |
| oxo | Ox Compiled Object |
| oxr | OPRO XML Report |
| ozf | Mozart Functor File |
| ozocode | Ozobot Program |
| p | MATLAB Compiled Program |
| p | OpenEdge ABL Procedure |
| p | ReaGeniX Code Generator Application Parameter |
| p1 | HI-TECH C Compiler Precompiled |
| p4a | Python for Android Script |
| p5 | Perl v5 Script |
| pa3 | Turbo Pascal for DOS Source Code |
| pack | µVision Software Package |
| package | Visual Studio SharePoint Package |