anchor.diff:  Billing Period:: The frequency in which Kill Bill invoices the account for one or more subscriptions. (_Examples:_ DAILY, WEEKLY, BIWEEKLY, MONTHLY, QUARTERLY, BIANNUAL, ANNUAL, BIENNIAL, and NO_BILLING_PERIOD)
   
   [[Bundle]]Bundle:: A collection of subscriptions associated with a single service instance. For example, a customer might have a base subscription for her phone, plus an add-on subscription for international dialing. Because both subscriptions are associated with the same phone, they are collected into a single bundle. An account may have several bundles, each with one or more subscriptions. Also known as a "subscription bundle."
  +
  +Bill Cycle Day:: The day of the month the invoice is created for an account. Note that this is applicable only to monthly and quarterly subscriptions.
   
   == C
   
  
positive.code: 
  External Key:: An alternative unique ID for an object, which you can use to map the object with an external resource. For example, you could define an external key for a specific customer account, which is the same as the identifier  used in your CRM system.
  
  _Example:_
  
  [cols="1"]
  
negative.code: 
  API:: The software intermediary that enables communication between two applications. For more information, see the https://killbill.github.io/slate/[_Kill Bill API Reference_].
  
  //Account Balance:: TODO
  
  // Account Credit::TODO
  
  
  == B
  
  Billing in Advance:: A type of https://docs.killbill.io/latest/catalog-examples.html#_billing_modes[billing mode] in which you can charge for services that are provided at a later date.
  