An ISO image (.iso) is a
disk image of an
ISO 9660 file system. ISO 9660 is an international standard originally devised for storing data on CD-ROM. More loosely, it refers to any
optical disc image, even a
UDF image.As is typical for disc images, in addition to the data
files that are contained in the ISO image, it also contains all the
filesystem metadata, including
boot code, structures, and attributes. All of this information is contained in a single file. These properties make it an attractive alternative to physical
media for the distribution of
software that requires this additional information as it is simple to retrieve over the
Internet.
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