The VirtualBox virtualization software was developed by InnoTek, which was taken over by Sun Microsystems in 2008.
It is used to virtualize various operating systems.
The software enables the operation of untailored guest systems and makes computer hardware (hard drives, graphics, sound, network cards, etc.) available to these systems in an emulated form. The processor and RAM are not emulated. Part of the RAM is permanently assigned to the guest system and an attempt is made to execute all the commands of the guest operating system directly on the host’s processor. Privileged processor commands are transferred to the host processor for execution after they are intercepted by the Code Scan and Analysis Manager (CSAM) and the patch manager (PATM). If necessary, VirtualBox can also use the hardware virtualization technologies provided by modern processors.
VirtualBox is compatible with Linux, Windows, macOS, as well as Solaris and OpenSolaris, and 32-bit as well as 64-bit x86 systems are supported as guest systems.
The VirtualBox is available in a closed source variant and as an Open Source edition (OSE). The source text for the Open Source edition can be downloaded from the project page .