Many archive formats compress the data to consume less storage space and result in quicker transfer times as the same data is represented by fewer bytes.
There are numerous compression algorithms available to losslessly compress archived data; some algorithms are designed to work better (smaller archive or faster compression) with particular data types.
Archive formats are used by most operating systems to package software for easier distribution and installation than binary executables.
Made obsolete by the introduction of AppleDouble-encoded 7z archives (Macintosh only).
.pak was also briefly used by the short lived MSDOS PKPAK program.