Best Free Software for Linux

Dolphin

A file manager for KDE (by default) and good for other desktop environments such as GNOME as well, focusing on usability with navigation bar, view properties, split of views, dockable panels and many other useful features.

FSlint

A convenient tool with both GUI and command lines modes to detect duplicate files and reclaim disk space. It also helps to identify unwanted or problematic file names, temporary files, bad symlinks, empty directories, nonstripped binaries and redundant whitespaces.

Clonezilla

Saves and restores only used blocks in the harddisk and increases the close efficiency. The version of Clonezilla Live is suitable for single machine backup and restore. (Review)

G4U ("Ghosting for Unix")

"Not only can it clone disk to disk (any size) and copy disk partitions, it can also create and restore image files both locally and from an FTP site, if the workstation is connected to a wired network with a DCHP service." (Review)

LuckyBackup

A useful tool to safely back up your data that you've changed in a source directory to a destination directory, or create multiple backup snapshots to a specific date and time. You can also use it to sync any directories to keep files identical on various devices.

Other features include options to exclude certain files, setting up profiles, scheduling and simulation controls.

Areca Backup

"Areca supports the typical full, mirror, incremental, and differential backup methods with several additional “storage modes” including a delta block mode. For compressed archives, it uses both Zip and Zip 64 with the choice of just about any encoding algorithm your heart desires. It allows you to place each backup in a single Zip archive, or a separate Zip for each file. Zip archives can be automatically split at any size you choose." (Review)

FreeFileSync

"A solid application with very clear and informative interface. The preview is very easy to understand, file collisions and deletions are readily recognizable.

If you require a sync program that can copy files that are in use or locked, it has you covered there too!" (Review)

Grsync

A graphical user interface for rsync and an effective tool to synchronize folders, files and make backups with support for sessions, simulation, execution, checksum, logging as well as other basic and advanced options for you to choose.

KDiff3

A convenient tool for you to compare two or three input files and show the differences line by line and character by character. It also provides an automatic merge facility and an integrated editor for comfortable solving of merge conflicts. (Review)

PeaZip

"Easy to use and very versatile, capable of creating 7Z, ARC, BZ2, GZ, PAQ/ZPAQ, PEA, QUAD/BALZ, TAR, UPX, ZIP files and extracting from 98 archive types." (Review)

File Roller and Ark

Both archive managers designed respectively for GNOME and KDE desktop environments to create archives, view or extract files from archives, work as front-ends to command-line archivers supporting various file formats.

GParted

"A GNOME partition editor for resizing (enlarging or shrinking), creating or deleting, moving or copying partitions on a hard disk, creating a partition table, enabling or disabling partition flags such as boot and hidden." (Review)

Parted Magic

"Employs core programs of GParted and GNU Parted to handle partitioning tasks and can be run from a live CD, DVD or USB flash drive." (Review)

TestDisk

"A console application designed for data recovery. It can be used to fix partition table, recover deleted partitions or copy files from deleted partitions." (Review)

Darik's Boot and Nuke

"Constructs a floppy disk or CD that will automatically wipe the hard drives of any PC that's booted from the disk, great for bulk disk cleaning and emergency." (Review)

TrueCrypt

"TrueCrypt is a powerful, flexible and highly-effective encryption program to encrypt files, folders or entire drives. Use this seasoned, widely-used encryption program when you want an encrypted container that mounts as a virtual drive.

It's one of those freeware programs that is far superior to commercial software and its open source status allows the all-important peer review of the source code required for a trustworthy encryption program." (Review)

GNU Privacy Assistant (GPA)

A useful tool with the graphical user interface for the GNU Privacy Guard (GnuPG or GPG) to encrypt, decrypt, sign files, verify signatures and manage the private and public keys.

Dvdisaster

"A preventive program to create an error correction file from a good CD or DVD for data recovery." (Review)

Dropbox

"Provides 2 GB free space for backing up and sharing your files, works similar to any other folder of your computer—after installation, simply drag and drop files/folders to Dropbox you want to backup, share or sync with other computer." (Review)

UltraCopier

"UltraCopier has some pretty exciting features including an excellent file resume option, which allows for resuming of a file transfer from a disconnected USB key. If you're in the middle of a file transfer from a USB key and it somehow becomes disconnected, when you plug it in again all you have to do is to hit resume and it will pick up where you left off!

It has also other useful options such as speed limitation and searching through the copy list. And as far as looks go, UltraCopier is a much more visually attractive copier replacement." (Review)

Unstoppable Copier

"Excellent for copying information from scratched CD's, DVD's and corrupted files from the hard drives." (Review)