An application data flow diagram is a graphical representation of the data flow in a business information system. Application data flow diagram describes the processes in a system to transfer data from the input to file storage and generate reports. There are two types of application data flow diagrams: logical and physical. The analytical data flow diagram depicts data flow through a system to perform specific business functions. The physical data flow diagram illustrates how the logical data flow is implemented. DFD graphically represents the functions or processes that capture, manipulate, store, and distribute data between a system and its environment and between system components.