You may know this as your "Account #" or your "Public Key". It is what you send people so they can send you ether. That icon is an easy way to recognize your address.
3. Print your paper wallet, or store a QR code version. (optional)
This is the unencrypted text version of your private key, meaning no password is necessary. If someone were to find your unencrypted private key, they could access your wallet without a password. For this reason, encrypted versions are typically recommended.
ProTip: Click print and save this as a PDF, even if you do not own a printer!
This is the unencrypted, JSON format of your private key. This means you do not need the password but anyone who finds your JSON can access your wallet & Ether without the password.