Visual representations sometimes help people understand concepts better. A system flow diagram is a way to show relationships between a business and its components, such as customers (according to IT Toolbox.) System flow diagrams, also known as process flow diagrams or data flow diagrams, are cousins to common flow charts. In a system flow diagram, the goal is to present a visual representation of some component of the business model, such as a standard customer/clerk transaction at a sandwich shop window.

Draw a circle to represent the external entity dealing with the business. In this example, label the oval “Customer.”

Draw a rectangle directly across from the oval. This represents the entity in the business that interacts with the external entity dealing with the business. In this example, label the box “Clerk.”

Connect the oval and the rectangle with arrows. Label the arrows with the actions or interactions taking place between the two components. In this example, you could write, “Make sandwich order” and “Exchange money.”

Describe what the business component does when a customer interacts with the business. Write these descriptions within the box containing the business component label. Here, under “Clerk,” you could write, “Take orders," “Meet customer demands” or “Tender change.”

Draw a second rectangle directly across from the business component box. This box represents the result of the interaction between the external entity and the business component. Here, you could label the box “Process Order” or “Make sandwich to order.”

Add more boxes and connect the boxes with arrows to flesh out the business component you are describing. System flow diagrams can be simple or complex, depending on the business component being described.