Items in APS are the different Raw Materials, Intermediates, Sub-Assemblies, and Finished Goods that are being produced, stocked, and consumed by the manufacturer. Whereas Inventory will deal mostly with the On-Hand and Safety Stock -- quantities of the Item -- the Item object will contain the Source of the Item, whether Manufactured or Purchased. Additional information is available for import, depending on the type of Item that is being imported. For example, if a particular Item is purchased or manufactured in batches, it may have a Minimum Order Quantity, which is the smallest acceptable quantity of that Item. Additionally, it may contain information on the expected lead time of that Item, and whether or not it has a Shelf Life, for Items that can spoil or deteriorate with time.
For information regarding the Shelf Life flag, click here.