Offline wallet:- Requires no password on the online computer to create.
Encrypted (Both online & offline):- Requires a password to sign transactions, image at bottom of thread of example.
No encryption:- Requires no password to sign transactions.
Image of three wallets:-
Example password box:-
Offline wallet is just a interface over the other two, so, if the offline computer has an encrypted wallet, you'll still need to enter the password there before you can sign it.