Any public catering facility (or a store) purchases materials to produce food as well as ready-to-eat items on a regular basis. In iiko, purchases are created by means of orders - special documents containing a list of required goods.
Orders placed with third-party vendors are referred to as external, orders send to own producing subdivisions - internal. As a general rule, only major companies have internal orders. Such companies have own distribution centers (DC).
For details, see the Production and Logistics article of iikoChain User Guide.
Internal orders are available only to chain restaurants using iikoChain.