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Creating a disk image
A disk image is a file that compresses and stores the contents of a disk (or part of a disk, such as a separate volume or folder). You can transger the disk image file to another disk or burn it on a CD or DVD as a way of moving files from one location to another.
You can use Disk Copy to create a disk image. You can make a blank image of any size or create an image of an existing device, folder, or volume.
Open Disk Copy (in Applications/Utilitiesand drag the item you want to make an image of to the Disk Copy window.
If you want to create a blank disk image, choose New from the File menu and Blank Image from the submenu. Type an image name and a volume name, and choose a size and disk format for the image. Choose Encryption if desired, then click Create.
A disk image name is followed by the filename extension ".dmg."
When you create a blank image, you can choose Mac OS, MS-DOS (Windows), or Unix format.
