| Abbreviation | Definition |
|---|---|
| X | Alysis SuperDisk Self-extracting archive |
| X | AVS X image file 24-bit Bitmap graphics |
| X | Lex language source code file |
| X | X1 Archive |
| X | X-file Animation ( Direct3D) ( DeepV2) |
| X01 | Paradox Secondary Index |
| X02 | Paradox Secondary Index |
| X03 | Paradox Secondary Index |
| X04 | Paradox Secondary Index |
| X05 | Paradox Secondary Index |
| X06 | Paradox Secondary Index |
| X07 | Paradox Secondary Index |
| X08 | Paradox Secondary Index |
| X09 | Paradox Secondary Index |
| X10 | X Window dump Bitmap graphics |
| X11 | X Window dump Bitmap graphics |
| X3D | x3d and xdart Formats |
| XA | The Sims - Electronic Arts |
| XAR | Corel Xara Drawing |
| XAR | XML Application Archive format |