LZMA2

LZMA2 is a compressed data format. It can be thought of as either a container format for LZMA, or as an improved version of the LZMA data format. Among other features, it allows different parts of the datastream to use different compression parameters.

It is used by the XZ file format, and is one of the available compression formats used by 7z.

Software

 * LZMA SDK

Links

 * Wikipedia: Lempel–Ziv–Markov chain algorithm - Has some information about LZMA2