rdiff-backup backs up one directory to another, possibly over a network. The target directory ends up a copy of the source directory, but extra reverse diffs are stored in a special subdirectory of that target directory, so you can still recover files lost some time ago. The idea is to combine the best features of a mirror and an incremental backup. rdiff-backup also preserves subdirectories, hard links, dev files, permissions, uid/gid ownership, modification times, extended attributes, acls, and resource forks. Also, rdiff-backup can operate in a bandwidth efficient manner over a pipe, like rsync. Thus you can use rdiff-backup and ssh to securely back a hard drive up to a remote location, and only the differences will be transmitted. Finally, rdiff-backup is easy to use and settings have sensical defaults.
All the programs which you install using Synapatic package manger,apt-get,aptitude have a .Deb file in the following folder
Dar is a shell command that makes backup of a directory tree and files. Its features include splitting archives over several files, CDs, ZIPs, or floppies, compression, full or differential backups, strong encryption, proper saving and restoration of hard links and extended attributes, remote backup using pipes and external command (such as ssh), and rearrangement of the "slices" of an existing archive. It can now run commands between slices, encrypt archives, and quickly retrieve individual files from differential and full backups. Dar also has external GUI like kdar for Linux,thanks to the well documented API.
If you want to create a system that is similar to a different system you have already set up, it can be difficult to remember each and every package you had installed.This method works best when you are exporting to and importing from the same distribution and, specifically, the same releasefor example, exporting from Ubuntu Dapper to Ubuntu Dapper or ubuntu edgy to ubuntu edgy.
dd_rhelp is a bash script that handles a very usefull program written in C which is called dd_rescue, it roughly act as the dd linux command with the caracteristic to NOT stop when it falls on read/write errors.

