Difference between dfd and flow chart?

The program flowchart describes boxes that describe computations, decisions, interactions & loops. It is an important to keep in mind that data flow diagrams are not program flowcharts and should not include control elements . A good DFD should * have no data flows that split up into a number of other data flows * have no crossing lines * not include flowchart loops of control elements * not include data flows that act as signals to activate processes.