alex@alex:~$ sudo aptitude show unrar
[sudo] password for alex:
Package: unrar
State: installed
Automatically installed: yes
Version: 1:4.0.3-1
Priority: optional
Section: multiverse/utils
Maintainer: Ubuntu Developers <[email protected]>
Uncompressed Size: 262 k
Depends: libc6 (>= 2.7), libgcc1 (>= 1:4.1.1), libstdc++6 (>= 4.1.1)
Conflicts: rar (<= 2.60-1)
Description: Unarchiver for .rar files (non-free version)
 Unrar can extract files from .rar archives. If you want to create .rar archives, install package rar.
Homepage: http://www.rarlabs.com/