What is the difference between a data flow diagram and a flow chart?

Question

I want to know why we use Data Flow Diagrams instead of flow charts.

Answer 1

A flow chart details the processes to follow. A DFD details the flow of data through a system.

In a flow chart, the arrows represent transfer of control (not data) between elements and the elements are instructions or decision (or I/O, etc).

In a DFD, the arrows are actually data transfer between the elements, which are themselves parts of a system.

Wikipedia has a good article on DFDs here.

Answer 2

You should use whatever you like. The diagram is just a tool. Use whatever tool fits you and your problem best. I usually just use boxes and arrows and squiggles and circles and little stick figures and whatever else I think gets the point across to the viewer. In short it doesn't matter if you even use a standard diagraming standard. People are usually pretty good at understanding pictures.

Answer 3

Data flow diagram shows the flow of data between the different entities and datastores in a system while a flow chart shows the steps involved to carried out a task. In a sense, data flow diagram provides a very high level view of the system, while a flow chart is a lower level view (basically showing the algorithm).

Whether you use data flow diagram or flow charts depends on figuring out what is it that you are trying to show.

Answer 4

The difference between a data flow diagram (DFD) and a flow chart (FC) are that a data flow diagram typically describes the data flow within a system and the flow chart usually describes the detailed logic of a business process.