Now we need to trade public keys with whomever we wish to email securely. So we export our public key.

gpg --export --armor john > john.asc

And then we import our friends public key.

gpg --import sally.asc

Now we list the keys again to make sure we see Sally's key.

gpg --list-keys

Finally we encrypt a message to send to Sally.

gpg -e message.txt

and we select Sally as a recipient.

Sally receives the file and decrypts it with the following command

gpg -d message.txt.gpg

and then enters her passphrase.