Non-inventory items refer to other types of items, such as those that are special ordered or drop-shipped to your customer. To create a new Non-Inventory Part item in QuickBooks Desktop Pro, open the “Item List” window. Then, track what you receive from vendors and what's still on order. An inventory item is a product that is purchased for resale and is tracked in Stock and on the Balance Sheet.
Basic types of inventory:
Work-in-progress (WIP) inventory.
Maintenance, repair & operations (MRO) goods.