KS3 (Years 7–9) · Computer Science
Computer Systems
What is it
A computer system is the combination of hardware (the physical parts — CPU, memory, storage, input/output devices) and software (the instructions that tell the hardware what to do) working together to process data.
Why it matters
Understanding how the parts of a computer fit together — not just how to use one — is the foundation everything else in Computer Science builds on. It's the difference between someone who can follow instructions on a screen and someone who understands why the screen is doing what it's doing.
Exam tip
When asked to describe a computer system, always mention both hardware AND software — a common mistake is describing only the physical parts and forgetting that instructions are just as essential.
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