Disk Utility, as its name implies, is a utility for management of hard drive, CD/DVD and compressed image files. Most of its advanced features, such as partitioning, formatting, cloning, partition table management are intended for power users of the operating system, however, the utility may be useful for an average Mac user with its basic features as well.
Basic user features include: information about a partition or a disk, burning an image to a disk, verifying file system, and enabling journaling for a particular partition or a hard drive.
Power users would be interested in the program ability to create, resize, and close images of hard drive or CD/DVDs. Disk erasing now supports "zero" write for secure wiping of the disk or a partition. The standard set of tools: permission management, image converter, MBR management, checking S.M.A.R.T. stats for a hard drive, restoring hard drives from an image are among most prominent power user features.
Utility interface is easy to navigate. A user can see physical and logical drives on the left side, its information to the right. Above there are options available for a particular partition. The options that cannot be applied to a particular drive, partition are grayed out and cannot be executed. The features are also mirrored in the File menu of the program with the system shortcuts to a particular option, in case there is something wrong with your mouse or you are lazy to repetitively click your mouse.
The program can be useful for the average users if there is something wrong with their CD/DVD or they need to configure their external hard drive the way they want. However, this program is not necessary used on a daily basis even for power users. It's a great tool to have it at hand, moreover for free.