| Abbreviation | Definition |
|---|---|
| IL | Inline expansion file (Fortran 90) |
| ILB | Data (Scream Tracker) |
| ILBM | Bitmap graphics (Amiga Interleaved Bitmap format) |
| ILK | Outline of program's format (incremental linker) (MS ILink) |
| IM | Bitmap graphics (Sun raster file) |
| IM1 | Bitmap graphics (1bit) (Sun raster file) |
| IM24 | 24bit Sun raster file Bitmap graphics |
| IM32 | Bitmap graphics (32bit) (Sun raster file) |
| IM8 | Bitmap graphics (8bit) (Sun raster file) |
| IMA | Mirage vector graphics ( EGO - Chart - Autumn) |
| IMA | WinImage Graphics |
| IMAGE | Disk Image (Disk Copy, ShrinkWrap) |
| IMG | Disk Image |
| IMG | GEM or ADEX Paint image format Bitmap graphics |
| IMP | IMP Compressed file archive |
| IMP | Pascal implementation |
| IMP | Spreadsheet (Lotus Improv) |
| IMQ | Image presentation (ImageQ) |
| IMQ | Planetary images by NASA (PDS format) |
| IMY | iMelody |