| laccdb | Microsoft Access 2007 Database Lock |
| latex | LaTeX Document |
| law | eLawForms Form Document |
| lay | Sprint-Layout Document |
| lay6 | Sprint-Layout v6 Document |
| lbi | Dreamweaver Library |
| lbl | P-touch Editor Document |
| lbl | Broderbund PrintMaster Label |
| lbx | P-touch Editor v5 Document |
| lbz | Leibniz Document |
| lch | IBM Works for OS/2 Chart |
| lcm | Label Designer Plus Document |
| lcw | Lucid 3-D Spreadsheet |
| ldf | Luratech Portable Document |
| ldr | LDraw Model File |
| lep | Label Designer Plus Document |
| let | Broderbund PrintMaster Letterhead |
| lgf | Imagine LogoMotion Image |
| lgx | Acornsoft Logistix Spreadsheet |
| lhd | Label Home Document |
| lhp | Lua Help Pages Document |
| li3d | Live Interior 3D Bundle Document |
| liquid | Shopify Liquid Template |
| lizd | Live Interior 3D Compressed Document |
| llb | Cadence OrCAD Layout |
| llg | LADSIM Ladder Logic Diagram |
| lmk | Sothink Logo Maker Logo |
| lms | LenMus Score Document |
| lmts | Pulsar LMTools Model |
| ln3 | DVILN03 Output File |
| lnb | PRO Landscape Planner Design Backup |
| lnf | PRO Landscape Planner Design |
| loe | LaTeX List of Theorems |
| logicly | Logicly Circuit Data |
| lot | LaTeX List of Tables |