ISO files are basically archive files that represent the contents written in every sector of an optical disk. This way you can have a CD or DVD image handy any time in your hard drive and use it accordingly (either mount it to access the data, or burn it on an actual physical disk). Linux users are very font of ISO files as this is the most common format that Linux distributions come in.
May 28, 2015
How to Handle ISO Files on Linux with Mount, AcetoneISO and Furious
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