Channel prefixes
When you sell through multiple channels, a per-channel prefix makes an order's origin readable at a glance. Each sales channel can override the default prefix from your order number settings; channels without an override inherit the default. The list shows a preview of each channel's resulting order number.
Inventory defaults
Two store-wide defaults for new products live here. Default allow backorder decides whether products with tracked inventory keep accepting orders at zero stock. Default max order quantity caps how many units of any single item one customer can order — leave it empty for no limit. Individual products can override both.