VirtualBox是德国一家软件公司InnoTek所开发的虚拟系统软件，它不仅具有丰富的特色，而且性能 也很优异。更是开源的，成为了一个发布在GPL许可之下的自由软件。VirtualBox 可以在 Linux 和 Windows 主机中运行，并支持在其中安装 Windows (NT 4.0、2000、XP、Server 2003、Vista)、DOS/Windows 3.x、Linux (2.4 和 2.6)、OpenBSD 等系列的客户操作系统。假如你曾经有用过虚拟机软件的经历的话，相信使用 VirtualBox 不在话下。即便你是一个新手，也没有关系。VirtualBox 提供了详细的文档，可以助你在短期内入门。
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更新日志：
VirtualBox 3.2.8 Final ：
VMM: properly terminate the VM with an error if the guest is trying to switch to the PAE mode but PAE is disabled in the VM settings
GUI: switch to native file dialogs (Windows hosts only; bug 5459)
GUI: don’t use native file dialogs on KDE hosts (Linux hosts only; bug 6809)
3D support: fixed GL_EXT_texture_sRGB support
PXE: fixed ZENworks PXE boot regression
OVF: fixed slower export and larger images under certain circumstances (3.2.6 regression; bug 7073)
USB: properly signal an interrupt if the port suspend status changes
USB: respect the remote-only filter
USB: avoid VM hang when changing the configuration of certain devices (Windows hosts only)
USB: fix a crash with older Linux kernels and non-ASCII characters in device strings (Linux hosts only; bug 6983)
PageFusion: fixed conflict with the guest execution feature
PageFusion: fixed stability issues with a large number of VMs
PageFusion: fixed host crashes with guest SMP and Win64 guests
Memory ballooning: fixed problems restoring VMs with pre-allocation enabled
Bridged networking: fixed performance issue with GRO enabled on bridged device (bug 7059)
Hostonly networking: fixed performance issue (3.2.6 regression; bug 7081)
Hard disks: fix auto-reset of immutable disk at VM startup (bug 6832)
BusLogic: several fixes for Windows NT/2000 and SCO OpenServer guests
LsiLogic: fixed I/O errors under rare circumstances
Sharing disks: support for attaching one disk to several VMs without external tools and tricks
Shared folders: several fixes and performance enhancements for Solaris guests (bugs 4154 and 6512)
Solaris Installer: added support for remote installations
Guest Properties API: correctly support enumerating the properties of a running VM with an empty "patterns" field (bug 7171)
Guest properties: properly delete transient properties on shutdown
RDP video redirection performance improvements and stability fixes
Settings: silently fix host audio driver when reading machine XML settings files or OVF written by VirtualBox on a different host OS, for example convert DirectSound to PulseAudio (bug 7209)
Settings: properly store the NAT network setting in XML settings file version 1.10 and later (bug 6176)
VBoxManage: handle differencing images with parent UUID correctly in subcommand openmedium disk (bug 6751)
Web service: enabled HTTP keepalive for much better performance
Web service: added timestamps to logging output
Web service: treat 8-bit strings as UTF-8 not ASCII
X11 Additions: fix for Xorg 6.8 guests (e.g. RHEL4)