Software Engineering › Key terms › Diagrams and tools › DFD external entity
DFD external entity
Diagram Diagrams and tools
Definition
A person, organisation or element that provides data to the system or receives data from it (shown as a rectangle).
Example: External entity: Customer.
Found in: course specifications, school notes, past SDD papers.
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.
- Multiple choice: Pick the option that matches the definition or example.
- Matching or table: Match it to its description, example or category.
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: DFD external entity 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: Drawing rules: DFD, structure chart, storyboard, decision tree, class diagram, ERD (Pseudocode, flowcharts and diagram rules)
How to use it in an answer
A model sentence
Diagram: “A person, organisation or element that provides data to the system or receives data from it (shown as a rectangle).” Then apply it: External entity: Customer.
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.
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.
- Multiple choice: Read all four options, rule out wrong ones, pick one; no penalty for guessing so never leave blank.
- Matching or table: Tick or match each statement to the right column (for example ORM v SQL, SAST v DAST).
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
- 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 data flow (labelled arrow) · Level 0 DFD (context diagram) · Level 1 DFD