| ldm | Sybase PowerDesigner Logical Data Model |
| ldml | Adobe GoLive LDML Data |
| ldmt | Likno Drop-Down Menu Trees Data |
| ldp | Active Directory Exported LDAP Data |
| ldp | Lingoes Dictionary Data |
| ldr | eSignal Hotlist Data |
| lds | Laser Dispatch Script |
| lds | VSE/VSAM Linear Data Set |
| ldsx | STAAD Advanced Concrete Design Cases and Combinations Data |
| ldt | EULUMDAT File |
| ldt | Oracle Generic Loader Data File |
| ldt | Zemax EULUMDAT Data |
| ldx | Lingoes Installed Dictionary Data |
| ldy | RAMAS Landscape Data |
| leases | DHCP Leases Database |
| led | AIBO LED File |
| lef | EnCase Logical Evidence Data |
| lef | LEN Exchange Format File |
| lei | Leica SP1 Image Session Data |
| lel | LayoutEditor Library Data |
| len | Esko PlatePrep Len File |
| lens | Autodesk Stitcher Camera Profile Data |
| leo | Leo Editor Outline Data |
| lepf | Little Endian Prebuilt Format File |
| ler | LopeEdit Results Data |
| les | LayoutEditor Schematic Data |
| les | Mklesson Lesson File |
| les | TurboWin LES Data |
| lesshst | Less History File |
| let | Genesis 2000 LET Data |
| let | Warrior List Export Template |
| lev | CARE-S InfoWorks Level Data |
| lev | ENVI Contour Levels Data |
| lev | Levelogger Software Data |
| lex | HP-71 Basic Extension |
