With VirtualBox, such a complex setup (then often called an “appliance”) can be packed into a virtual machine. For example, installing a complete mail server solution on a real machine can be a tedious task. Software vendors can use virtual machines to ship entire software conﬁgurations. Since you can conﬁgure what kinds of “virtual” hardware should be presented to each such operating system, you can install an old operating system such as DOS or OS/2 even if your real computer’s hardware is no longer supported by that operating system. This way, you can run software written for one operating system on another (for example, Windows software on Linux or a Mac) without having to reboot to use it.

VirtualBox allows you to run more than one operating system at a time.

VirtualBox provides are useful for several scenarios: Running multiple operating systems simultaneously. The powerful virtualization product for enterprise as well as home use. Targeted at server, desktop and embedded use, it is now the only professional quality virtualization solution. VirtualBox is a general-purpose full virtualizer for hardware.

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