What is a disk file and how do I open a disk file?
DISK is a disk image file that serves as a virtual hard disk for Linux operating systems, such as Ubuntu, Kubuntu, Xubuntu, Edubuntu, and UbuntuStudio. It can be mounted and viewed by the operating system as an actual hard disk, and can be used to run multiple variations of Linux without needing to repartition the hard drive.
Relevant disk file links:How to open disk file on Youtube
How to open disk file on Wikipedia
How to open disk file on Microsoft.com