WinRAR:

WinRAR is a shareware file archiver and data compression utility developed by Eugene Roshal and distributed by Alexander Roshal, first released in autumn of 1993. It is one of the few applications that is able to create RAR archives natively, because the encoding method is held to be proprietary. Command-line versions, simply called "RAR", exist for Mac OS X, Linux, and FreeBSD.

WinRAR supports the following features:
Complete support for RAR (WinRAR native conversion format) and ZIP archives, and unpacking of ARJ, LZH, TAR, GZ, ACE, UUE, BZ2, JAR, ISO, EXE, 7z, Z, and xz archives.
Multithreaded compression
The ability to create self-extracting and multi-volume (split) archives.
Data redundancy is provided via recovery records and recovery volumes, allowing reconstruction of damaged archives.
Support for advanced NTFS file system options and Unicode in file names.
Optional archive encryption using AES (Advanced Encryption Standard) with a 256-bit key.

In the past a portable version of WinRAR called WinRAR Unplugged existed. It didn't require installation, nor did it create dependencies on the host computer.

Developer(s):              Eugene Roshal, Alexander Roshal
Development status:   Current
Written in:                  C++
Operating system:             Up to and including 3.93: Windows 95, 98, Me[2]
                                        Up to and including 4.11: 2000
                                        Current releases: XP, Vista, 7, 8
                                        Supported via Wine: Mac OS X, FreeBSD, Linux and other  POSIX OSes
License:                      Commercial, Proprietary, Shareware

WinRAR in Windows 7

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