A pack may refer to any of the following:
The process of bunching information together into one file, causing all the data to occupy less space on the storage device. Once the data is packed, it can be unpacked back to its original location.
Linux command, see the pack command page for additional information.
Compress, Software terms, Unpack
Use of pack is generally deprecated; modern compression utilities such as gzip have taken its place, although Huffman coding is still widely supported.
