A Supplier is a company you buy ingredients from. Suppliers are attached to ingredients (Supplier Default and Supplier IDs), group the Inventory Shopping List, receive order emails and are chosen when importing receipts. They require the Suppliers module and live at Settings > Kitchen Settings > Suppliers. A Vendor is a producer/partner attached to meal recipes so you can report sales per vendor (Reports > Meals by Vendor). Vendors require the Vendors module, are managed per kitchen location at Settings > Kitchen Settings > Vendors, and have only a Name and an Active/Inactive status.