7-Zip

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7-Zip is a file archiver with the highest compression ratio. The program supports 7z, ZIP, RAR, CAB, ARJ, LZH, CHM, CPIO, RPM, DEB, GZIP, BZIP2, Z and TAR formats. Compression ratio in the new 7z format is 30-50% better than ratio in ZIP format. Also 7-Zip compresses to ZIP 2-10% better than PKZip and WinZip. 7-Zip has additional powerful command line version and FAR Manager support.