Open DMG File

ISO File

ISO is a file extension used by disk image files stored in ISO 9660 or UDF (ISO/IEC 13346) file formats. ISO images are typically used to store optical disk images and could be used to burn CDs, DVDs or Blu-Ray disks. Technically ISO is similar to a full backup of an optical disk, though it doesn’t store all disk specific information like error correction and control headers. Thus they do not create a 100% replica of the original disk. There are also certain limitation that ISO format pose since it does not support tracks information. So if original disk has multiple tracks it won't be properly stored in ISO formats and workarounds like CUE/BIN, CCD/IMG and MDS/MDF formats will be needed to store information properly.

ISO is a popular method to distribute operating systems to developers and end users. For example Microsoft uses ISO files to distribute its Windows 10 OS to users. It is possible to download ISO file with a full Windows build from Microsoft Windows ISO page and burn it to USB drive or DVD.

Most of the virtual machines also provide support to ISO file format since ISO file is the most convenient method of operating system distribution. In order to setup a new operating system on virtual machine you will need to connect ISO file as a virtual drive and run installation from there.

Windows, Mac OS and Linux all support mounting ISO files but only Mac OS and Linux has built-in capabilities to create ISO files. To create ISO file on Mac OS you can use disk utility software (select File->New->Disk Image from Device menu to create a .cdr file and then use hdiutil to convert .cdr file to .iso).

On Linux you can use following command to create ISO file.

sudo dd if=/dev/cdrom of=/home/username/example.iso