Levels in Data Flow Diagrams (DFD) .
In Software engineering DFD(data flow diagram) can be drawn to represent the system of different levels of abstraction. Higher level DFDs are partitioned into low levelshacking more information and functional elements. Levels in DFD are numbered 0, 1, 2 or beyond. Here, we will see mainly 3 levels in data flow diagram, which are: 0level DFD, 1level DFD, and 2level DFD.