4. Software
System vs application software, the operating system, interrupts, and how high-level languages become machine code.
In the 2029–31 syllabus this is Topic 5, with much more on how the operating system manages memory, files, processes and devices, and IDE features incl. AI assistance. What changes in 2029 → · Study the new topic: 5. Software
Statometer71CoreNext Paper 189%Everything for this topic — study hub
O Level / IGCSE · 2210 · 0478 · Paper 1
This topic is rows 13–14 of the study route.Open it on your study route
Statometer — what 25 real papers say about this topic and each of its 2 syllabus bullets
Core · #7 of 10 in O Level / IGCSE · recomputed with every new session
A regular, well-paid topic — you cannot afford a gap here.
- Next Paper 1
- 89%
- 9 in 10 chance it is set
- Marks a paper
- 11.8 / 75
- 16% of Paper 1 · fair share 17%
- Appeared in
- 23 / 25
- Paper 1 sittings 2023–2026
- Last set
- May/Jun 2026
- 0478/13 · Q5 · 9 marks · 11-series streak
What the papers say
- Set in 23 of 25 Paper 1 sittings on the current syllabus — treat it as certain.
- Worth about 11.8 marks a paper (16% of Paper 1).
- Last set May/Jun 2026 · 0478/13 · Q5 for 9 marks — in the most recent series.
- Set in each of the last 11 series without a miss.
- Rising: about 7.8 marks a paper in the earlier years, 14.9 in the latest.
- Lives on “Give” and “State” — 66% of its questions: short, precise answers in syllabus words.
- Most of its marks (78%) come in extended questions of 6+ marks — plan the answer before writing.
- Its biggest question so far: 22 marks (May/Jun 2025 · 2210/12 · Q3).
- Inside the topic, §4.2 Programming languages, translators and IDEs carries the most marks (64%) and §4.1 Types of software and interrupts the least (36%).
- It is examined mostly as AO1 (Knowledge & understanding, 72%) — definitions and descriptions in syllabus words score.
- The examiner has commented on 61 of its questions — read “What the examiner said” before you practise.
Command words
Share of questions using the word (a question can use several). What each wants →
Question shapes
- 1–2 mk0
- 3–4 mk23
- 5–6 mk24
- 7–9 mk18
- 10+ mk22
Average 7.3 marks a question · 8% with a figure or table · 24% with code · biggest 22 marks
Assessment objectives — how it is examined
Every part of every current-syllabus question filed under Cambridge's AO1 / AO2 / AO3 (from its command word and what it asks you to do), so you know whether this topic pays for definitions, for applying, or for judging and building.
- AO1 Knowledge & understanding
- AO2 Apply to a context
- AO3 Evaluate & judge
Paper 1 as a whole
| Paper 1 | Syllabus | Measured |
|---|---|---|
| AO1 Knowledge & understanding | 60% | 64% |
| AO2 Apply to a context | 20% | 24% |
| AO3 Evaluate & judge | 20% | 12% |
Syllabus = Cambridge's grid; measured = the bank's current-syllabus papers.
Inside the topic — every syllabus bullet, measured
Each part of each question is filed under the bullet it examines; the numbers are per Paper 1 sitting, exactly like the topic's. Open a bullet for its own Statometer.
4.1Types of software and interrupts#10 of 20 on Paper 1Core · 5964% next paper3.6 marks17/25 sittings↘ May/Jun 2026Core · 5964%
3.6 · 36% of topic17/25May/Jun 2026latest series · ↘A regular earner inside the topic — most papers touch it.Syllabus: system vs application software; functions of an operating system; hardware, firmware and the bootloader; how interrupts are generated and handled by the ISR
- Next Paper 1
- 64%
- 6 in 10
- Marks a paper
- 3.6
- 5% of the paper · 36% of the topic
- Asked in
- 17 / 25
- Paper 1 sittings · 40 questions
- Last asked
- May/Jun 2026
- 2210/11 · Q4 · 4 marks · 4-series streak
- Asked in 17 of 25 Paper 1 sittings — about 7 papers in 10.
- About 3.6 marks a paper (5% of Paper 1; 36% of the topic's marks across its 2 bullets).
- Last asked May/Jun 2026 · 2210/11 · Q4 (4 marks) — in the most recent series.
- Asked in each of the last 4 series.
- Easing: 4.4 → 3.1 marks a paper.
- Usually “Give” or “State”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 10 in Feb/Mar 2024 · 0478/12 · Q3.
- It is examined almost entirely as AO1 (Knowledge & understanding, 87%) — definitions and descriptions in syllabus words score.
Last 12 sittings↘ EasingAssessment objectives
AO1 87%- AO1 Knowledge & understanding
- AO2 Apply to a context
- AO3 Evaluate & judge
- Give55%
- State53%
- Describe40%
- Complete23%
4.2Programming languages, translators and IDEs#7 of 20 on Paper 1Core · 6764% next paper4.7 marks15/25 sittings↗ May/Jun 2026Core · 6764%
4.7 · 64% of topic15/25May/Jun 2026latest series · ↗A regular earner inside the topic — most papers touch it.Syllabus: high-level vs low-level languages; assembly language and assemblers; compilers vs interpreters and how each reports errors; functions of an IDE
- Next Paper 1
- 64%
- 6 in 10
- Marks a paper
- 4.7
- 6% of the paper · 64% of the topic
- Asked in
- 15 / 25
- Paper 1 sittings · 49 questions
- Last asked
- May/Jun 2026
- 0478/13 · Q5 · 6 marks · 6-series streak
- Asked in 15 of 25 Paper 1 sittings — about 6 papers in 10.
- About 4.7 marks a paper (6% of Paper 1; 64% of the topic's marks across its 2 bullets).
- Last asked May/Jun 2026 · 0478/13 · Q5 (6 marks) — in the most recent series.
- Asked in each of the last 6 series.
- Rising: 2.7 → 6.4 marks a paper.
- Usually “Give” or “Describe”: short, precise answers in syllabus words.
- Biggest chunk of marks so far: 11 in May/Jun 2025 · 2210/12 · Q3.
- It is examined as a mix: AO1 50%, AO2 34%, AO3 16% — definitions and descriptions in syllabus words score.
Last 12 sittings↗ RisingAssessment objectives
AO1 50%AO2 34%AO3 16%- AO1 Knowledge & understanding
- AO2 Apply to a context
- AO3 Evaluate & judge
- Give41%
- Describe37%
- Explain37%
- State33%
24% of the topic's marks sit in question parts that belong to another topic (scenario questions cross sections) or that no bullet claims; they count for the topic, not for a bullet.
Marks a paper, year by year
Grey years are the previous syllabus (2010–2022, 54 questions) — history, not counted in the rates.
By exam series
- Feb/Mar4/4 · 11.8 mk
- May/Jun12/12 · 11.2 mk
- Oct/Nov7/9 · 10.1 mk
What you need to know2syllabus §4.1, §4.2
- 4.1Types of software and interrupts — system vs application software; functions of an operating system; hardware, firmware and the bootloader; how interrupts are generated and handled by the ISR
- 4.2Programming languages, translators and IDEs — high-level vs low-level languages; assembly language and assemblers; compilers vs interpreters and how each reports errors; functions of an IDE
Video lectures14ZAK's YouTube channel · play here
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Infographics3draw these the way the examiner expects · download as PNG
How an interrupt is handled
Compiler, interpreter & assembler
What the operating system does
Key terms9use these exact words in the exam
Dotted terms are defined in the glossary.
Code help2referenced to the Cambridge pseudocode guide
How an interpreter behaves: stop at first error
textLine 1: DECLARE X : INTEGER ✔ executed Line 2: X ← 5 ✔ executed Line 3: OUTPUT X + ✖ syntax error — execution stops here Line 4: OUTPUT "done" never reached A compiler would report the Line 3 error (and any others) and produce no executable at all.
Try it: a deliberate error in the Playground (this one is meant to fail)
pseudocode Run in PlaygroundDECLARE X : INTEGERX ← 5OUTPUT XOUTPUT Y // Y was never DECLAREd — see the error message
Test yourself
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NewCS Games · 16 to play
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