| lums | SAP Lumira Document |
| lumx | SAP Lumira Discovery 2.0 Document |
| lvw | Livewire Document |
| lwc | Legacy Charting Chart Document |
| lwd | LotusWorks Text Document |
| lwl | DYMO Label Document |
| Lightwright Printed Paperwork Formatting Instructions |
| lwo | Lightwave 3D Object |
| lwob | Lightwave 3D Object |
| lwp | IBM Works for OS/2 Document |
| Legato Word Processor Document |
| Lotus Word Pro Document |
| lws | Lightwave 3D Scene |
| lwsc | Lightwave 3D Scene |
| lwt | DYMO Label Template |
| lxe | Luxology Modo 3D Scene |
| lxf | LEGO Digital Designer Model |
| lxfml | LEGO Digital Designer Model |
| lxo | Luxology Modo 3D Image |
| ly | GNU Lilypond Document |
| ly+ | DataCAD Plus Layer Data |
| lyc | bestIMAGE Compressed Design |
| lyr | bestIMAGE Layer Data |
| lyt | Proteus Electronics Layout |
| lyx | LyX Document |
| lyz | LaserDRW Document |
| m15 | thinEdge M15 File |
| ma | Autodesk Maya 3D ASCII Scene |
| Mathematica ASCII File |
| ma2 | Winplot Mapping Document |
| maca | MacWrite Document |
| macdraw | MacDraw Drawing |
| macmol | MacMolecule Document |
| maf | Microsoft Access Form |
| mag | Microsoft Access Diagram Shortcut |
| magic | SlideMagic Presentation Document |
| maj | Autodesk Fabrication Job |
| makerbot | MakerBot 3D Print Document |
| mam | Microsoft Access Macro |
| man | Unix Manual Page |
| manu | Lotus Manuscript v1 Document |
| maple | Maple Workbook Document |
| maq | Microsoft Access Query |
| mar | Mariner Calc Document |
| Microsoft Access Report |
| marc | MARC Document |
| mars | Adobe MARS Document |
| mas | Microsoft Access Stored Procedure |
| mass | MASS-11 Text Document |
| mat | Microsoft Access Table |
| mathml | Mathematical Markup Language Document |
| mau | Microsoft Access Function Shortcut |
| mav | Microsoft Access View Shortcut |
| maw | Microsoft Access Data Access Page |
| max | Autodesk 3D Studio Max Scene |
| Cadence OrCAD Max Layout |
| Microsoft Creative Writer Document |
| OmniPage Scanned Document |
| mb | Autodesk Maya 3D Binary Scene |
| Mathematica Binary File |
| mb3 | Minimal Board Editor Document |
| mb4 | Model Builder Document |
| mbb | ManaBook Document |
| mbbk | ManaBook Book Kit |
| mbf | Microsoft Money Backup |
| mbk | SmartWare Macro Backup |
| mbxml | meBible XML File |
| mc2 | MasterCook 5 CookBook |
| mc7 | Mastercam 7 Document |
| mc8 | Mastercam 8 Document |
| mc9 | Mastercam 9 Document |
| mcbn | Microsoft Excel 4 for Mac Chart |
| mcd | Mathcad Document |
| VectorWorks Drawing Document |
| mcdx | Mathcad Prime Document |
| mcf | MasterCook CookBook File |
| mcl | VectorWorks Drawing Template |
| mcm | MacMolecule Document |
| mcpat | myriaCross Editor Design Document |
| mcr | C.a.R. Macro |
