Auto-renewal is when your credit card or PayPal account is charged on a recurring basis upon subscription expiration. If you selected automatic renewal during sign up the recurring subscription fee will continue until you cancel. You may cancel via your account settings or by contacting firstname.lastname@example.org.
PayPal accounts, in order to be eligible for auto-renewal, must have a credit card associated with them. Presently, PayPal doesn't allow those residing in Germany or China to utilize auto-renewal.