Data Flow Model

As information converts data through software, it is modified by a series of transformations. These transformations are then depicted through a graphical representation of processes that are applied as data transforms the input it receives by creating a data flow output.

A data flow diagram takes business processes and activities and uses them to create a clear illustration of how data flows through a system. DFDs represent the flow of data from external entities into a single system by moving and storing data from one process to another.

Through the use of data flow diagrams, a system can be decomposed into subsystems, and subsystems can be further decomposed into lower-level subsystems. Each subsystem represents a process or activity in which data is processed. Once the lowest level is reached, processes can no longer be decomposed.

Data flow modeling can be used to identify a variety of different things, such as:

• Information that is received from or sent to other individuals, organizations, or other computer systems.
• Areas within a system where information is stored and the flows of information within the system are being modeled.
• The processes of a system that act upon information received and produce the resulting outputs.