Cambridge (CIE) IGCSE · Computer Science
Cracking the Exam Papers
Big idea: Your IGCSE Computer Science grade comes from two equally-weighted
1h45m papers — Paper 1 tests what you about how computers work,
and Paper 2 tests whether you can to solve problems —
and knowing exactly how each paper is built is half the battle before you even revise the content.
Summary — The Whole Picture in 60 Seconds
- Two papers, equal weight: Paper 1 (50%) and Paper 2 (50%) — together they make up 100% of your IGCSE grade. There's no coursework or non-exam assessment.
- Same shape, different focus: Both papers are 1 hour 45 minutes, both worth 75 marks, both written papers with short-answer and structured questions, and in , every single question is compulsory — you can't skip anything.
- Paper 1 = the "how computers work" paper: data representation, data transmission, hardware, software, the internet, and emerging tech (Topics 1–6).
- Paper 2 = the "think like a programmer" paper: algorithm design, programming, databases, and Boolean logic (Topics 7–10) — this is where you write actual pseudocode.
- No calculators allowed in either paper — so your binary/hex conversions and arithmetic need to be exam-ready by hand.
- Same three assessment objectives (AOs) run through both papers: AO1 (know it), AO2 (apply it), AO3 (evaluate and conclude).
- Paper 2's final question is unique: a 15-mark unseen scenario where you write a full algorithm — budget 30 minutes for it alone.
- Syntax isn't examined — examiners care about your , not whether you remembered a semicolon.
Paper 1 — Theory of Computer Systems
What is Paper 1 actually testing?
Think of Paper 1 as the "under the hood" paper. It's not really asking you to
anything with a computer — it's asking whether you understand
how a computer system is built and how it functions, from the way a single
character gets turned into binary, all the way up to how your phone talks to a
web server on the other side of the world. It's a knowledge-and-understanding-heavy
paper, though it still expects you to apply that knowledge to real-life ICT contexts
rather than just recite facts.
Paper 1 — Key Facts
Duration: 1 hour 45 minutes | Marks: 75 |
Weighting: 50% of the IGCSE | Calculator: Not permitted |
Grade range covered: A* to G
The six topics Paper 1 covers
Every question on Paper 1 is drawn from Topics 1 through 6 of the syllabus, and — importantly — each question is dropped into its own real-world ICT scenario, rather than being asked abstractly.
Topic 1Data Representation
Topic 2Data Transmission
Topic 3Hardware
Topic 4Software
Topic 5The Internet and its Uses
Topic 6Automated and Emerging Technologies
How the paper is structured
It's a written paper made up of short-answer and structured questions —
meaning you'll see a mix of one-line factual answers and longer, multi-part questions
that build on each other. You answer directly on the question paper (there's no
separate answer booklet), and critically, every question is compulsory — there's
no "answer 3 out of 5" choice like you might get in some other subjects. That means you
genuinely need to revise the whole syllabus, not just your favourite topics.
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