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What is Data Flow Diagram ?

What is Data Flow Diagram ?

Data Flow Diagram :  Data flow Diagram is Graphical Representation of flow of data in a information system. it is  also known as bubble chart . The main Reason why DFD is so popular technique because it is very simple to draw and also simple to understand and it is use . A DFD Model is very limited number of primitive  symbol for represent the function of the system and the Data flow.

Type of  DFD : data flow diagram are two type

  • Logical DFD : The logical dataflow diagram describes flow of data though a system.
  • Physical DFD : The Physical dataflow diagram describe the implemention of the logical data flow. 
DFD Symbol :


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