order type

There are four options and system settings determine if two, three or four are displayed for selection.

Reserve Order – allocates stock but cannot be processed until changed to Invoice Order. Back order records are not created until sales order is processed
Invoice Order – allocates stock and can be processed. Back order records are only created when the form has been processed
Forward Order - does not take stock, does not create back order records and cannot be processed. There are utilities that are used to manage Forward ordering Forward Order Processing and Forward Order Scheduling
Active Order – allocates stock, back order records are created on saving of the form and the sales order can only be processed from the sales order screen. The form must be changed to an Invoice Order to be processed from the menu. Process Back Orders will run stock into an ‘unprocessed’ active order multiple times – any snapshot before the sales order is processed.

Invoicing system settings control what options are available and the default order type when creating new sales orders.

DefaultOrderType - minimum options are Invoice Order and Reserve Order. Forward Orders and Active Orders are available if those settings are enabled (see next two points)
AllowForwardOrders - enables this functionality
AlowActiveOrders - enables this functionality