TrueCrypt is software for establishing and maintaining an on-the-fly-encrypted volume (data storage device). On-the-fly encryption means that data is automatically encrypted or decrypted before it is loaded or saved, without any action on your part. No data stored on an encrypted volume can be read (decrypted) without using the correct password/keyfile(s) or correct encryption keys. Entire file system is encrypted (e.g., file names, folder names, contents of every file, free space, meta data, etc).

This is great software for laptops. But be aware that if you lose the password, the data is gone forever. Use with caution.

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