Question

What is dfd ? give its utility in system development?

Answer 1

A data flow diagram (DFD) is a graphical representation of the "flow" of data through an information system, modelling its processaspects. A DFD is often used as a preliminary step to create an overview of the system without going into great detail, which can later be elaborated.[2] DFDs can also be used for the visualization of data processing(structured design).[citation needed]

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 flowchart which focuses on control flow, or a UML activity workflow diagram, which presents both control and data flows as a unified model.[citation needed]