The main feature of 7-Zip is high compression ratio in new 7z format with LZMA compression.
Supported formats are o Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR; o Unpacking only: ARJ, CAB, CHM, CPIO, DEB, DMG, HFS, ISO, LZH, LZMA, MSI, NSIS, RAR, RPM, UDF, WIM, XAR and Z.
For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip; strong AES-256 encryption in 7z and ZIP formats; self-extracting capability for 7z format; integration with Windows Shell.
It also includes powerful File Manager; powerful command line version; plugin for FAR Manager; localizations for 74 languages.
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Shadow-Box
Good compressing zip program.
Guest #37702406
7-zip is the best compression tool. I like it.
Monnie
This is a great and very easy to use. 