Disk Encryption Software

Disk encryption software is computer security software that is designed to protect the confidentiality of the data stored on a computer disk by utilizing a technique called disk encryption. Compared to access restrictions commonly enforced by an OS, this technique allows data be to be protected even when the OS is not active, for example, if data are read directly from the hardware. Such software encrypts data stored on a computer's mass storage and transparently decrypts the information when an authorized user requests it: no special action by the user (except supplying a password or passphrase at the beginning of a session) is required. Some also provide plausible deniability with deniable encryption techniques.

The volume-level encryption is particularly suited to portable devices such as laptop computers and thumb drives. If used properly, someone finding a lost device will have access only to inaccessible encrypted files. A strong passphrase (e.g. five or more diceware words) is essential for full security.

While disk encryption software can transparently operate on an entire disk volume, a directory, or even a single file, non-transparent file encryption software only encrypts or decrypts whole, individual files and stores the decrypted file in a temporary file. Some examples of file encryption software are GNU Privacy Guard and PGP). File archivers, and even some text editors such as emacs or vi can encrypt files.