A disk image is a file that contains an exact copy of your hard disk. The Linux operating system uses the “dd” command to create disk images. The “dd” command copies the hard drive bit by bit, so the disk image is the exact same size as the hard drive. To make the file smaller, you can use the “gzip” command to compress it. To make an image of your main hard drive, you must have a Linux Live CD, such as Knoppix. Writer Bio
