Systems analysis notation: in computer-based information systems (CBIS), what does DFD stand for?
Correct Answer: data flow diagram
Introduction / Context:Systems analysts use diagramming techniques to capture and communicate how information moves through processes and data stores. One of the foundational tools is the DFD, a standardized way to depict processes, data stores, external entities, and the flows between them. Knowing this acronym is essential for reading and producing analysis documents.
Given Data / Assumptions:
- We are within CBIS/SDLC context involving structured analysis.
- DFD is a long-standing, widely taught notation.
- We distinguish it from unrelated or made-up phrases.
Concept / Approach:A data flow diagram represents systems at varying levels of detail (context diagrams, level-0, level-1). Arrows denote data flows, bubbles/rectangles denote processes, open-ended rectangles denote data stores, and squares represent external entities. DFDs focus on what data moves where, not on physical hardware or control flow timing.
Step-by-Step Solution:
Recall the standard expansion of DFD → data flow diagram. Eliminate distractors that are not standard terminology. Confirm relevance to CBIS and structured analysis. Select “data flow diagram.”Verification / Alternative check:Structured analysis texts and methodologies (e.g., Yourdon–DeMarco) define DFD precisely as “data flow diagram,” confirming this choice.
Why Other Options Are Wrong:
- Data flow descent / dotted flow diagram: not recognized analysis terms.
- Terminology does not exist: false; DFDs are foundational.
- None: incorrect because the correct term is present.
Common Pitfalls:Confusing DFDs with ER diagrams (which model data structures) or UML activity diagrams (which model control flow and activities).
Final Answer:data flow diagram