If you've ever downloaded a disk image file in .ISO format, then you'll know that you need a means of mounting these on the system as the OS itself won't do it automatically.
For Windows, I use OSFMount, which supports .ISO and a great many other image file formats such as .IMG, .BIN, .NRG, .SDI, .VMDK and more.
OSFMount also supports formatting, extending, imaging and the creation of RAM disks.
Alternative solutions are Virtual Clonedrive and Daemon Tools Lite, although the latter is only free for non-commercial use.
Mac OS X
For Mac OS X, you can mount .ISO images using Apple's Disk Utility application, which can be found in the
/Applications/Utilities folder, as follow...
- Open Disk Utility
- Select the Open Disk Image... option from the File menu
- Locate your disk image and click on the Open button to mount it
hdiutil mount sample.iso
where sample.iso is the path to the image you want to mount.