When you purchase a package, a fixed number of credits are assigned to your account. Those credits may be either for certain specific classes, or a fixed number of classes under a certain dollar limit. The latter are referred to as dollar value credits.
IMPORTANT (PLEASE READ)- After purchasing a package, you must sign up for individual class times. Return to the instructor's studio and you will see the word "Credit" next to each upcoming class that you can attend. Click the "Credit" button and follow the steps to sign up for the upcoming class.
Also see, How Do I Check My Credits?