With virtual machines, it is possible to run Tails inside a *host* operating system (Linux, Windows, or macOS). A virtual machine emulates a real computer and its operating system, called a *guest*, which appears in a window on the *host* operating system.
<p>We only mention Free Software, because we believe that it is a necessary condition to be trustworthy. Proprietary virtualization software exist, such as <i>VMWare</i>, but is not listed here on purpose.</p>
<p>We are not recommending <i>VirtualBox</i> anymore because only basic functionalities of Tails work in <i>VirtualBox</i>, for example, the display size is limited to 800×600 pixels.</p>
