Free open-source disk encryption software for Windows Vista/XP, Mac OS X, and Linux .
We are pleased to announce that TrueCrypt 6.0 has been released.

This version introduces parallelized encryption and decryption on multi-core processors (or multi-processor systems). Increase in encryption/decryption speed is directly proportional to the number of cores and/or processors. For example, on a quad-core processor, encryption and decryption is four times faster than on a single-core processor with equivalent specifications [view benchmark results].

This version also introduces the ability to create and run an encrypted hidden operating system whose existence is impossible to prove (provided that certain guidelines are followed), the ability to encrypt an entire system drive even if it contains extended partitions, a new volume format that increases reliability, performance and expandability, and more.

Main Features:
Creates a virtual encrypted disk within a file and mounts it as a real disk.
Encrypts an entire partition or storage device such as USB flash drive or hard drive.
Encrypts a partition or drive where Windows is installed (pre-boot authentication).
Encryption is automatic, real-time (on-the-fly) and transparent.
Provides two levels of plausible deniability, in case an adversary forces you to reveal the password:
1) Hidden volume (steganography – more information may be found here).
2) No TrueCrypt volume can be identified (volumes cannot be distinguished from random data).
Encryption algorithms: AES-256, Serpent, and Twofish. Mode of operation: XTS.

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