When a customer has finished shopping and wants to purchase the items in their remote shopping cart, they typically click an HTML button on a web site labeled, for example, Proceed to Checkout. This button must submit the value of the PurchaseURL, which is returned by all cart operations except CartClear. Once the customer clicks this button, the items in the Active area are emptied from the shopping cart and entered into the Order Pipeline.

This chapter explains how to submit the contents of a remote shopping cart for purchase in the following sections.