Purpose of a Data Flow Diagram


A Data Flow Diagram (DFD) is a diagrammatic representation of the information flows within a system showing
  • How information enters and leaves the system 
  • What changes the information 
  • Where information is stored

The purpose of a DFD is
  • To show the scope and boundaries of a system 
  • To show that the whole system has been considered
  • May be used as a communications tool between a systems analyst and any person who plays a part in the system
  • To act as the starting point for redesigning a system 

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