What is top down approach in DFD?

The top-down approach in Data Flow Diagrams (DFD) involves breaking down a system into its high-level components and then progressively detailing each component into smaller, more specific processes. This method starts with a broad overview of the system, represented by a high-level DFD, and gradually refines it into lower-level diagrams that illustrate the specific data flows and processes. This hierarchical structure helps in understanding the overall system while ensuring clarity and organization in design. It is particularly useful for identifying relationships and interactions within complex systems.