7-Zip is open source software. Most of the source code is under the GNU LGPL license. The unRAR code is under a mixed license: GNU LGPL + unRAR restrictions. Check license information here: 7-Zip license.
You can use 7-Zip on any computer, including a computer in a commercial organization. You don't need to register or pay for 7-Zip.
The main features of 7-Zip:
High compression ratio in new 7z format with LZMA compression
Supported formats:
Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
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
Powerful File Manager
Powerful command line version
Plugin for FAR Manager
Localizations for 74 languages
7-Zip works in Windows 7 / Vista / XP / 2008 / 2003 / 2000 / NT / ME / 98. There is a port of the command line version to Linux/Unix.
Other Info: Noctua chipset cooler fitted with after market cooling also fitted to VRMs on the Motherboard.
11-22-2010
A Version 9.20 of the free 7-Zip archival utility has been released. This major update contains a range of changes including support for LZMA2, XZ and PPMd, updating of solid .7z archives, speed optimizations, as well as bug fixes.
Storage Devices: SAMSUNG 830 SATA III 64GB SSD, SAMSUNG F3 HD502HJ 500 GB, SAMSUNG F3 HD502IJ 500 GB,
External HDD: 2 x SAMSUNG F3 HD103SJ 1TB, SAMSUNG MP4 HM250HJ 250GB
Other Info: Corsair H60 Water Cooler, Samsung CD/DVD-RW SH-S223F 22X burner Black OEM, Lian-Li PC-7F Black Anodized All-Aluminum Mid-Tower Case, Logitech Cordless Trackman Wheel
11-22-2010
Ross - I merged your thread with the one started by Cliff in the Free Software database so that since this is an update to 7Zip it would be in the thread.
Hope you don't mind... keeps things a little tidier.