zlib

zlib is a compression/decompression library that is built into many languages and tools such as Java, Python, .NET, PHP, Perl, Ruby, Swift, Go,

In Git, zlib is apparently used to create pack files.

zlib is part of the core of the Linux Standard Base.

The data formats that zlib manages are described in RFCs 1950, 1951 and 1952.

Homepage: http://zlib.net/