Working with Disks - Teach Yourself Visually Complete Mac Pro - page 734

Copy a Hard Drive to a Disk Image
You can make a backup of a hard drive by copying the contents of the drive to a disk image.
A disk image is a special file that contains the contents — the structure, folders, and files —
of a hard drive. A disk image is also useful if you want a straightforward way to send the con-
tents of a hard drive to another person. You learn how to view a disk image in OS X in the
next section, “ Mount a Disk Image . ”
Copy a Hard Drive to a Disk Image
Click Spotlight ( ).
Type disk .
Click Disk Utility .
The Disk Utility window appears.