I haven't used PGP since way back in the day, so I can't help you with the actual program, but the way the keys work is like this. To encrypt or decrypt data you use a key which is a bunch of numbers or characters, the program creates a pair of keys for you, a private key and a public key. You then give out your public key to anyone who wants to send you a secret. They use your public key to encrypt the secret and send you the scrambled mess. Then you receive the scrambled mess and use your private key to decrypt it. It's like a box that anyone can put something in and lock with the locking key, but you're the only one that can open it with the unlock key. Hope this helps, it's pretty much necessary to know at least this much before you can use public key cryptography.