What this how-to covers:
Setting up seahorse/nautilus integration
Generating a GPG key using a terminal
Using the key with nautilus-seahorse plugin to encrypt/decrypt files
What this how-to does not cover:
Everything else, including:
What is PGP,GPG,RSA and how does it work?
If you are not familiar with these topics or encryption in general, please read through some articles online. It is important to have at least basic understanding of how it works to be able to use it in a safe way.
To watch this How-To as a screencast-video click here
Generate GPG Key
You will have to enter a passphrase to protect your key.
This passphrase should be easy to remember, yet impossible to guess.
Something like “ninjas like 2 juggle with baby pigs & eat watermelons at 3pm”
Make sure to remeber the passphrase, once its gone, its gone, and so is your chance to use the key you just created (and any files encrypted using it).
Encrypt a file using your new key
The encrypted file will be saved as “.pgp”.
Decrypt the file
To decrypt the file, right-click and choose “Open With Decrypt File”
Choose where the decrypted file should be saved to.
Again, you will be prompted to enter the passphrase.
You now have 3 files: the original(plain text), the encrypted (scrambled)and the encrypted-then-decrypted(plain text) file.