The re-order function allows you to quickly repeat your previous orders. These functions are available only when you are logged into the system. This function has two options: repeating previous orders and reordering from a saved orders list.
Repeating previous orders simply loads an order you have placed from your order history. Saved orders are orders that you have saved but have not necessarily submitted. To access these features, log in or create an account, then click on "My Account" in the upper-right corner of the site.