The term packing is (in some communities, at least) often used as a synonym for data compression. It could also refer to the process of combining multiple files into one (archiving). There are many formats and utilities that have pack in their name, or that are described as packers.
"Pack" can also be short for package, which could imply an installer format, or a transfer format.
This page does not list every format with "pack" in its name. Other places to look:
- Audio and Music
Pack or packed might refer to:
- pack (Unix) (.z)
- PACK - an executable compression utility for DOS by "NoddegamrA" 
- RLE90 (e.g. in ARC)
- Git packfile (.pack)
- Package (Web) (.pack)
- Macintosh type code
Packmight mean Diamond.