dd, that stands for ‘data duplicator’, is a command-line utility for Unix mainly used for copying and converting data. This tool can be used for: • Backing up and restoring an entire hard drive or a partition. • Copy regions of raw device files like backing up MBR (master boot record). • Converting data formats like ASCII to EBCDIC. • Converting lowercase to uppercase and vice versa. • Creating files with fixed size.
- dd just copies byte by byte without any analysis of the content while clonezilla prevents copying empty areas by checking the content.