In this example, the Supplier, Kitchen, Manager, and Customer are the entities who will interact with the system. It also shows the participants who will interact with the system, called the external entities. It contains a process (shape) that represents the system to model, in this case, the ' Food Ordering System'.

The figure below shows a context Data Flow Diagram that is drawn for a Food Ordering System. Some of the benefits of a Context Diagram are: At this level, there is only one visible process node that represents the functions of a complete system in regards to how it interacts with external entities. The Food Ordering System Example Context DFDĪ context diagram is a data flow diagram that only shows the top level, otherwise known as Level 0.