What is the purpose of a Data Flow Diagram?

A Data Flow Diagram (DFD) serves the primary purpose of illustrating the flow of data within a system. It visually represents how data moves from one part of the system to another, showing the relationships between different processes and data stores. By using various symbols—like circles for processes, arrows for data flow, and open-ended rectangles for data stores—DFDs provide a clear and concise depiction of how information is processed and transferred within an organization.

This visualization aids stakeholders, such as business analysts and developers, in understanding the interactions and data requirements of a system at a high level. By mapping out these flows, the diagram can help identify potential inefficiencies or areas for improvement within the data handling processes.

The other choices, while related to information systems, do not capture the primary function of a Data Flow Diagram. For instance, representing storage capacity relates more to database design than to how data flows, while defining backup procedures is focused on data preservation rather than its movement. Lastly, user interface design analysis pertains to the visual aspects and usability of software, distinct from the data flow aspects that DFDs address.