Virtual Disk Images Files
|Developer:||Sun Microsystems, Inc.|
VirtualBox is a program used for Computer Virtualization, this allows you to create a computer that in reality isn't there. The virtual Computer uses the hardware that is in your computer and uses a file for the hard drive. The program supports various platforms and due to being available as open source software is free to use for professional and home use.
The files that are used by VirtualBox for your virtual computer are stored in a disc image that has the .vdi file extension, these are Virtual Disk Images files which basically act as the hard drive for the virtual computer.