In computing, 7z is an archive format which allows data compression using a number of compression algorithms. The format was initially implemented by the 7-Zip archiver but the file format is public and 7-Zip's implementation of it is publicly available under the GNU LGPL licence.
The main features of the 7z format are:
- Open, modular architecture (which allows any compression, conversion, or encryption method to be used)
- High compression ratio (depending on which compression method is used)
- Strong AES-256 encryption
- Support for large files (up to approximately 16000 petabytes)
- Unicode file names
- Compression of archive headers
- LZMA - Improved and optimized version of LZ77 algorithm
- PPMD - Dmitry Shkarin's PPMdH with small changes
- BCJ - Converter for 32-bit x86 executables
- BCJ2 - Converter for 32-bit x86 executables
- Bzip2 - Standard Burrows-Wheeler algorithm
- DEFLATE - Standard LZ77-based algorithm