Encryption scares a lot of people – me included – because it’s based on really complicated mathematics. Thankfully, the state of encryption software has advanced sufficiently in the last couple of years that it’s pretty easy for laypeople like us to take advantage of the protection it offers. Just like you don’t shop online without a secured HTTPS connection, you really ought not engage in private conversations online without encrypting your messages. When you encrypt your messages, you don’t need to worry so much about a college kid hacking into your Yahoo! account when you’re appointed to some high office: sure, they might get into your account, but the contents of your messages are still protected. And in this age of cloud computing, when we’re never entirely sure where any particular bit of our data might be, nor who might have access to it, encryption starts to look even more attractive.
I recommend GnuPG, the GNU Privacy Guard, the free (as in speech) implementation of the Pretty Good Privacy standard developed by Phil Zimmerman, and the FireGPG add-on for Mozilla Firefox. The great thing about this combo is that it works on GNU/Linux, Mac OSX and Windows. GnuPG uses a public key infrastructure, which takes two keys to properly encrypt anything. One key is public, which you give to everyone and anyone. The other key is private, which you must absolutely keep protected: if your private key is ever compromised, then your encrypted messages might as well be posted to Wikileaks for the world to see. Folks use your public key to encrypt a message that only you can decrypt. You use your private key to do that decrypting.
