TrueCrypt

TrueCrypt is a software application used for on-the-fly encryption. It can create a virtual encrypted disk in a file (container), which can be mounted as if it were a real disk. TrueCrypt also supports device-hosted volumes, which can be created on either an individual partition or an entire disk. As of version 5.0, it can encrypt the Windows boot partition or entire boot drive. It is distributed under the TrueCrypt Collective License. TrueCrypt is available for Microsoft Windows, Mac OS X, and Linux.

Encryption algorithms supported by TrueCrypt: AES-256, Blowfish (448-bit key), CAST5, Serpent (256-bit key), Triple DES, and Twofish (256-bit key). Supports cascading (e.g., AES-Twofish-Serpent).

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