A Disk Image is a mirror of your logical drive that is stored in one file. It can be useful if you want to backup the contents of the entire drive (partition), and restore it or work with it later. Before you start recovering the deleted files, it may be a good idea to create a Disk Image for this drive, if you have enough space at another drive. Why? Because if you do something wrong while recovering files (for example, recovering them onto the same drive can destroy their contents), you still will be able to recover these deleted files and folders from the Disk Image that you have wisely created. Images are very important for data recovering from damaged partitions.