These both provide very solid email encryption that is protected against even the most sophisticated cracking attempts. It is likely that anything is crackable if “they” really want to crack it, but this is the strongest encryption known as this current time and is believed to be secure.
How does it work?
The technology is pretty cool. You have a public key for encryption and a private key for decryption. You can share your public key with the world and all they can use it for is to encrypt email to you.
Here’s the cool part: that same public key that encrypted the email cannot decrypt the email. Only your private key can do that. It’s actually a one-way encoding key. The only way to reverse it is with the private key, which only you hold.
There are currently servers which can hold your public key, if you want to make it publicly available. This way, anyone can find you and send you encrypted email.
Note: It would fantastic to see people get over the initial hump of setting this up and begin using it exclusively. This goes back to being secure in our persons, papers, houses, and effects, as the constitution mentions. Just because you aren’t hiding something doesn’t mean that you need to reveal everything. Privacy is key.