The ISO file format is pretty much entranched in the PC world as THE format to use for CD/DVD disk images. The advantages of this format are plenty – It is a standard open format and tools to work with it are readily available for all operating systems, Windows, Unix/Linux and OS X.
While Mac users can use the ISO format on their machines, Most software on OS X is distributed as a DMG file. The DMG file format has a couple of arguable advantages over the ISO format like encryption, compression etc., but the truth is that the rest of the world uses ISO and there is no way easy way to use DMG files in the PC world.
