The data flow diagram is for analyzing ___________________.
The data flow diagram is for analysis requirements of user.
A Data Flow Diagram (DFD) is traditional visual representation of the information flows within a system. A neat and clear DFD can depict a good amount of the system requirements graphically. It is usually beginning with a context diagram as the level 0 of DFD diagram, a simple representation of the whole system.
A DFD is often used as a preliminary step to create an overview of the system without going into great detail, which can later be elaborated. DFDs can also be used for the visualization of data processing(structured design). A DFD shows what kind of information will be input to and output from the system, how the data will advance through the system, and where the data will be stored.