I hear that using PGP involves passphrases. What are they and do I need to use them?
Similar to a password, a passphrase uses a sentence and a neumonic reminder that aids in creating and remembering strong passwords. PGP on a Mac uses passphrases to authenticate your identity. ITS recommends that PGP on Windows be synchronized to your Windows logon credentials instead of creating a passphrase. See step 14 in the Windows Installation, Configuration, and Encryption document.