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Level 1 DFD
Diagram Check Diagrams and tools
Definition
Breaks the single process of the Level 0 diagram into its main processes and shows data stores and flows between them.
Example: Process 1 Borrow book, process 2 Return book, data store Loans.
Check this one: The course specification gives the Level 0 diagram; Level 1 as a refinement is standard practice. Check how your teacher draws it.
Where it is used in the test
Syllabus area: Diagrams and tools.
Question types it can appear in
- Drawing: Draw or label it in the online drawing tool.
- Short answer: Define, outline or explain it and tie it to the scenario.
Where it has appeared in the paper
The Software Engineering Project (Part D). Part letters follow each paper’s own layout.
Related past questions
- 2024 Software Design and Development HSC Q24 (10 marks): Social and ethical issues The Software Engineering Project (Part D) · 10 marks · old syllabus
These are the questions the flashcard set links to this term. Open each one and compare your answer with its marking criteria.
Study links
- Flashcard: Level 1 DFD in Diagrams and Modelling Tools (Years 11 and 12) · study that set
- Memorise: Drawing rules: DFD, structure chart, storyboard, decision tree, class diagram, ERD
- Notes: Modelling tools: DFD, structure charts, storyboards, flowcharts, class diagrams (The Software Engineering Project (Year 12))
How to use it in an answer
A model sentence
Diagram: “Breaks the single process of the Level 0 diagram into its main processes and shows data stores and flows between them.” Then apply it: Process 1 Borrow book, process 2 Return book, data store Loans.
In a short answer, give the definition in your own words first, then tie it to the situation in the question. Do not copy the example above unless it fits the scenario.
Command words used with it
No linked question shows the command word for this term. Across the past drawing and short answer questions in this bank the words used most are: Explain, Outline, Describe, Compare, Classify, Analyse. Check the actual word in your question.
Technique for the question types
- Drawing: Use the online drawing tool: label every symbol and arrow, use the correct symbols from the specification, and add every required item.
- Short answer: One clear point per mark, use the stimulus and course terms, and answer the command word.
What the marking guidelines and feedback say
Old-syllabus question. Use for practice on the overlapping skill only. The new Software Engineering exam does not use the old SDD terms (e.g. CASE tools, system flowcharts, EBNF, assembly).
Common mistakes
- Check the sources: The course specification gives the Level 0 diagram; Level 1 as a refinement is standard practice. Check how your teacher draws it.
- Drawing questions (2025 HSC exam Q22): refine attributes into separate inherited classes; use appropriate class diagram symbols.
- Use the term exactly as the syllabus words it, then link it to the scenario in the question; the 2025 feedback repeatedly rewards using the stimulus.
- Answer the command word: outline gives main points only, explain gives a reason or cause, discuss gives both sides.
Related terms
Same group in the syllabus: Data flow diagram (DFD) · DFD process (circle) · DFD data store · DFD external entity · DFD data flow (labelled arrow) · Level 0 DFD (context diagram)