Wikipedia
Partclone
Partclone is a partition clone and restore tool. It provides utilities to back up and restore partitions and is designed for higher compatibility of the file system library. It is developed by the NCHC Free Software Labs in Taiwan. It is the default backup application in Clonezilla, FOG from version 1.00 and Redo Backup and Recovery which is simply a front end to partclone. It supports many file systems and has good performance, as it skips portions of the file system marked as free space.