Data flow diagram-数据流图

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. It does not show information about process timing or whether processes will operate in sequence or in parallel, unlike a traditional structured flowchartwhich focuses on control flow, or a UML activity workflow diagram, which presents both control and data flows as a unified model.^{[citation needed]}

 

https://en.wikipedia.org/wiki/Data_flow_diagram