Applications like rsnapshot rotate a snapshot to the next level by creating a hard-linked copy. Creating a hard-linked copy may seem like a good idea but it is still a waste of disk space, since only files can be hard-linked and not directories. The duplicated directory structure can take up as much as 100 MB of space.

Timeshift is similar to applications like rsnapshot, BackInTime and TimeVault but with different goals.

rsnapshot.... it uses rsync for the backup, very good setup