Payment terms can be as simple as a due date and a discount date and rate, or they can include payment schedules to allow for several installment payments.
Payment schedules appear on the Customer tab of the Invoice Entry screen when you use a terms code that has been set up to use a multiple payment schedule.
All payment terms are defined in Accounts Receivable, but you can change the terms for an order or an invoice on the Customer tab of the Invoice Entry screen.