This is the software publisher's description.
Powerful x86 virtualization products for enterprise as well as home use. Not
only is VirtualBox an extremely feature rich, high performance product for
enterprise customers, it is also the only professional solution that is freely
available as Open Source Software under the terms of the GNU General Public
License (GPL). See "About VirtualBox" for an introduction; see "innotek" for
more about our company.
Presently, VirtualBox runs on Windows, Linux, Macintosh and OpenSolaris hosts
and supports a large number of guest operating systems including but not limited
to Windows (NT 4.0, 2000, XP, Server 2003, Vista), DOS/Windows 3.x, Linux (2.4
and 2.6), and OpenBSD.
VirtualBox is being actively developed with frequent releases and has an ever
growing list of features, supported guest operating systems and platforms it
runs on. VirtualBox is a community effort backed by a dedicated company:
everyone is encouraged to contribute while innotek ensures the product always
meets professional quality criteria.
On the VirtualBox site, you can find sources, binaries, documentation and
other resources for VirtualBox.
Version 2.0 ships with major enhancements such as 64-bit support, stronger
networking capabilities and a native Mac OS X interface (Mac OS X version).