How to Encrypt
Some popular encryption applications are PGP (Pretty Good Privacy), TrueCrypt, IPSec, SafeHouse, BitLocker, CryptoForge, Secure House, Advanced Encryption Package, and more. Such applications allow users to encrypt email messages, personal files, folders, and even the entire hard disk or USB drive.
Select an application that works on the operating system in use. Also, consider how these applications encrypt data. Some applications change the file format independent of the file system. Other such as TrueCrypt install a mountable encrypted file with its own internal file system, and still others such as BitLocker build the encryption into the real file system.
Web browsers automatically encrypt information when it connects to a secure website, as depicted by the https:// prefix, as opposed to standard http:// prefix. Popular email clients provide encryption programs as plug-ins or interfaces, allowing users to encrypt emails.
Windows XP has an Encrypting File System (EFS) feature that allows storing files in an encrypted format on hard disks, formatted NTFS volumes. Linux Operating systems such as FreeBSD/Solaris have a .gpg command that serves as an encryption and signing tool.