zlib
zlib is the DEFLATE compression library (RFC 1950) maintained by Jean-loup Gailly and Mark Adler, providing an in-memory compression API; it underlies gzip.
Purpose
It gives applications an embeddable DEFLATE compression/decompression API with multiple compression levels and flush strategies.
Mechanism
A DEFLATE core plus a 2-byte header (CMF, FLG) and an ADLER32 checksum trailer. The API supports streaming compression, memory-level selection, and three wrappers: raw, deflate, and gzip.
Use cases
- PNG image encoding
- HTTP compression
- OpenSSL TLS compression