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Encrypt whole disks, removable media, software RAID, partitions, files and logical volumes.
Pro Native Linux support
It offers the best integration and ease of use on Linux.
Pro Free and open-source
Open-source for cryptography is a requirement, not just a bonus.
Pro Support for multiple keys/passwords
If several people should be able to decrypt a volume, each one can have their own password/key.
Con Requires advanced command line knowledge
In order to use dm-crypt you need to have advanced knowledge of Linux and of the command line, as well as the Linux filesystem.
However, most distros support easy creation of LUKS-encrypted drives when installing Linux transparently.