TrueCrypt is a free open-source disk encryption software for Windows XP/2000/2003 and LinuxTrueCrypt Features:
. It can create a virtual encrypted disk within a file and mount it as a real disk.
. It can encrypt an entire hard disk partition or a device, such as USB memory stick, floppy disk, etc.
. Provides two levels of plausible deniability, in case an adversary forces you to reveal the password:
. TrueCrypt volume cannot be identified (no part of the volume can be distinguished from random data).
. Encryption algorithms: AES (256-bit key), Blowfish (448-bit key), CAST5 (128-bit key), Serpent (256-bit key), Triple DES, and Twofish (256-bit key). Supports cascading (e.g., AES-Serpent-Twofish).
. Based on Encryption for the Masses (E4M) 2.02a, which was conceived in 1997.