-Full Disk Encryption (FDE): Encryption of as much of the hard drive as possible and still boot. Usually has to leave a “boot” partition unencrypted to allow system to boot far enough to decrypt the rest of the drive.
-LUKS: a disk-encryption specification created by Clemens Fruhwirth in 2004 and originally intended for Linux.
-dm-crypt: a transparent disk encryption subsystem in Linux kernel versions 2.6 and later and in DragonFly BSD.
Tor–Tor is free software for enabling online anonymity.
Tails–Privacy for anyone anywhere.
GPG–The GNU Privacy Guard (GnuPG) is a free replacement for PGP.
PGP–Pretty Good Privacy is a data encryption and decryption computer program.
Jitsi–Encrypted video/audio and chat. Secure alternative to Skype.
Cryptool–Free e-learning site for cryptography and cryptoanalysis