Some Common File Extensions
| Extension | Description | O/S | Type | Notes/Comments |
| abe | ASCII-Binary Encoding | Unix | B | encodes binary files (executables, for instance) for transmission over text only (Email) channels |
| arc | archive | DOS | B | pkarc, arc |
| arj | archive | DOS | B | arj |
| bin | MacBinary | Mac | B | Stuffit |
| c | C Source Code | Any | A | ASCII Text |
| com | program | DOS | B | executable |
| cpt | text | | | |
| doc | text or WP file | Any | B | Usually Microsoft Word |
| eps | encapsulated postscript | | | |
| exe | program | | | |
| gif | Graphic Interchange Format | | | Graphic file format from Compuserve |
| gz | compressed | | | |
| hqx | translation format for sending binary files via email | Mac | B | BinHex |
| jpg, jpeg, jpe | Graphic file | Any | B | Graphic File format from the Joint Photographic Experts Group |
| lha, lhz | archived/compressed | DOS | B | use lha or lharc |
| mpg, mpe, mpeg | film or video clip | Any | B | Graphic File format from the Motion Picture Experts Grou |
| pit | | | | |
| ps | | | | |
| sea | | | | |
| shar | | | | |
| sit | | | | |
| tar | | | | |
| tgz | | | | |
| trf | | | | Unix |
| txt | | | | |
| uu, uue | | | | |
| wp | | | | |
| z | compressed | Unix | B | Unix pack format |
| Z | compressed | Unix | B | Unix compress format |
| zip | | | | |
| zoo | | | | |
| | | | |
| | | | |
