I've gone through the set-up steps, but am now looking for a basic description of how this pgp works on my recepients' end of things.
Do I need to give them a key, or will they be able to read my emails without it?
Is the passphrase that I created when setting up the account the same key that I would need to give my recepients for them to read my emails?
If the recipient has encryption set up, nothing special is needed. Just use the "Secure Compose" to write them an encrypted message.
Your pass phrase that you set up earlier should always stay private, don't share that with anyone.
Anytime you write someone who doesn't seem to have encryption set up, the recipient email will turn grey (in Secure Compose). These messages will have to be protected with an additional password that you share with the recipient (you'll be prompted for one if needed).