A VirtualBox or VB is a software virtualization package that installs on an operating system as an application. VirtualBox allows additional operating systems to be installed on it, as a Guest OS, and run in a virtual environment. In 2010, VirtualBox was the most popular virtualization software application. Supported operating systems include Windows XP, Windows Vista, Windows 7, macOS X, Linux, Solaris, and OpenSolaris.
VirtualBox was originally developed by Innotek GmbH and released in 2007 as an open-source software package. The company was later purchased by Sun Microsystems. Oracle Corporation now develops the software package and titles it Oracle VM VirtualBox.