5. System Software
Operating systems and utilities, language translators, compilers vs interpreters, IDE features.
Statometer75BankerNext Paper 188%Everything for this topic — study hub
AS Level · 9618 · Paper 1
This topic is rows 16–17 of the study route.Open it on your study route
Statometer — what 33 real papers say about this topic and each of its 2 syllabus bullets
Banker · #7 of 12 in AS Level · recomputed with every new session
Set in nearly every paper and worth a big slice of it — revise first, expect it.
- Next Paper 1
- 88%
- 9 in 10 chance it is set
- Marks a paper
- 12.5 / 75
- 17% of Paper 1 · fair share 13%
- Appeared in
- 31 / 33
- Paper 1 sittings 2021–2026
- Last set
- May/Jun 2026
- 9618/13 · Q5 · 10 marks · 11-series streak
What the papers say
- Set in 31 of 33 Paper 1 sittings on the current syllabus — treat it as certain.
- Worth about 12.5 marks a paper (17% of Paper 1, 1.3× its fair share).
- Last set May/Jun 2026 · 9618/13 · Q5 for 10 marks — in the most recent series.
- Set in each of the last 11 series without a miss.
- Easing off: about 15 marks a paper earlier, 11.8 in the latest years — still examined, just smaller.
- Lives on “Describe” and “Explain” — 78% of its questions: full sentences with a reason, not one-word answers.
- 36% of its questions involve a diagram, table or figure — practise with pen and paper.
- Its biggest question so far: 22 marks (May/Jun 2024 · 9618/13 · Q7).
- Inside the topic, §5.1 Operating systems carries the most marks (63%) and §5.2 Language translators the least (37%).
- It is examined almost entirely as AO1 (Knowledge & understanding, 90%) — definitions and descriptions in syllabus words score.
- The examiner has commented on 59 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
- ≤ 6 mk20
- 7–9 mk20
- 10–12 mk24
- 13–15 mk9
- 16+ mk8
Average 9.5 marks a question · 36% with a figure or table · 17% 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 & analyse
- AO3 Design, program & evaluate
Paper 1 as a whole
| Paper 1 | Syllabus | Measured |
|---|---|---|
| AO1 Knowledge & understanding | 60% | 68% |
| AO2 Apply & analyse | 40% | 32% |
| AO3 Design, program & evaluate | 0% | 0% |
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.
5.1Operating systems#8 of 25 on Paper 1Banker · 7768% next paper5 marks24/33 sittings↘ May/Jun 2026Banker · 7768%
5 · 63% of topic24/33May/Jun 2026latest series · ↘Asked in nearly every paper — the bullet to know cold.Syllabus: why an OS is needed; memory, file, security, hardware and process management; utility software (formatter, virus checker, defragmenter, backup…); program libraries and DLLs
- Next Paper 1
- 68%
- 7 in 10
- Marks a paper
- 5
- 7% of the paper · 63% of the topic
- Asked in
- 24 / 33
- Paper 1 sittings · 58 questions
- Last asked
- May/Jun 2026
- 9618/13 · Q5 · 10 marks · 11-series streak
- Asked in 24 of 33 Paper 1 sittings — about 7 papers in 10.
- About 5 marks a paper (7% of Paper 1; 63% of the topic's marks across its 2 bullets).
- Last asked May/Jun 2026 · 9618/13 · Q5 (10 marks) — in the most recent series.
- Asked in each of the last 11 series.
- Easing: 6.8 → 4.5 marks a paper.
- Usually “Describe” or “Explain”: full sentences with a reason, not one-word answers.
- Biggest chunk of marks so far: 11 in Oct/Nov 2021 · 9618/12 · Q7.
- It is examined almost entirely as AO1 (Knowledge & understanding, 98%) — definitions and descriptions in syllabus words score.
Last 12 sittings↘ EasingAssessment objectives
AO1 98%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- Describe55%
- Explain50%
- Identify43%
- State36%
5.2Language translators#12 of 25 on Paper 1Core · 6666% next paper3.8 marks23/33 sittings↘ May/Jun 2026Core · 6666%
3.8 · 37% of topic23/33May/Jun 2026latest series · ↘A regular earner inside the topic — most papers touch it.Syllabus: assemblers, compilers and interpreters; compiling vs interpreting; partial compilation (Java); IDE features for coding, error detection, presentation and debugging
- Next Paper 1
- 66%
- 7 in 10
- Marks a paper
- 3.8
- 5% of the paper · 37% of the topic
- Asked in
- 23 / 33
- Paper 1 sittings · 41 questions
- Last asked
- May/Jun 2026
- 9618/12 · Q7 · 6 marks · 11-series streak
- Asked in 23 of 33 Paper 1 sittings — about 7 papers in 10.
- About 3.8 marks a paper (5% of Paper 1; 37% of the topic's marks across its 2 bullets).
- Last asked May/Jun 2026 · 9618/12 · Q7 (6 marks) — in the most recent series.
- Asked in each of the last 11 series.
- Easing: 5 → 3.5 marks a paper.
- Usually “Describe” or “Explain”: full sentences with a reason, not one-word answers.
- Biggest chunk of marks so far: 9 in Oct/Nov 2023 · 9618/11 · Q6.
- It is examined almost entirely as AO1 (Knowledge & understanding, 82%) — definitions and descriptions in syllabus words score.
Last 12 sittings↘ EasingAssessment objectives
AO1 82%AO2 18%- AO1 Knowledge & understanding
- AO2 Apply & analyse
- AO3 Design, program & evaluate
- Describe59%
- Explain59%
- Identify46%
- State22%
26% 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 (2015–2021, 46 questions) — history, not counted in the rates.
By exam series
- May/Jun17/18 · 14.2 mk
- Oct/Nov14/15 · 13 mk
What you need to know2syllabus §5.1, §5.2
- 5.1Operating systems — why an OS is needed; memory, file, security, hardware and process management; utility software (formatter, virus checker, defragmenter, backup…); program libraries and DLLs
- 5.2Language translators — assemblers, compilers and interpreters; compiling vs interpreting; partial compilation (Java); IDE features for coding, error detection, presentation and debugging
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Infographics2draw these the way the examiner expects · download as PNG
Compiler, interpreter & assembler
What the operating system does
Key terms8use these exact words in the exam
Dotted terms are defined in the glossary.
Code help1referenced to the Cambridge pseudocode guide
What the translator stages see
textSource: Total ← Price * Qty + 5 Lexical: [ID Total] [ASSIGN] [ID Price] [OP *] [ID Qty] [OP +] [NUM 5] Syntax: assignment( Total , plus( times(Price, Qty), 5 ) ) ← parse tree Code gen: LDD Price / MUL Qty / ADD #5 / STO Total Optimise: e.g. keep Price*Qty in a register if reused
Assembler1programs to step through the CPU simulator
- Run
Symbolic addresses (labels) instead of numbers
Label your data and jump targets — the assembler turns each label into an address. Check the memory panel to see where NUM1 landed.
Test yourself
Ready to check you know it?
Every round is a fresh random draw, weak cards come back until you get them right, and past-paper questions come with their mark schemes. Marks earn XP on your dashboard.
NewCS Games · 16 to play
Revise this topic by playing
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