Lessons in this series
Work through in order - each lesson builds on the last.
1
What does a computer actually do?
Start with the big picture. Before naming any components, understand the single thing every computer does: fetch, decode, execute. We anchor this in the real world before getting technical.
2
Inside the CPU
Zoom in. The ALU, control unit, registers and buses - but explained through what each one actually does, not just what it is called. Includes the interactive FDE Visualiser.
3
Why is your CPU faster than mine?
Clock speed, cores, cache size and pipelining. Why do these affect performance? Compare real chips and understand the trade-offs engineers make when designing a processor.
4
The memory problem
Why can't we just use one type of memory for everything? Explore the speed-cost-capacity trade-off that forces us to use RAM, ROM, cache and registers in a hierarchy.
5
Storing data long-term
HDDs, SSDs, optical discs and flash storage. Which technology suits which job and why? Grounded in real decisions - from hospital tape archives to gaming laptops.
Exam practice
5 MCQ questions and 3 written exam questions. Includes printable worksheets and a timed 35-mark exam paper.
Flashcards
Test your recall of all 27 key terms. Filter by lesson, flip to reveal definitions, and track what you know.
Computer Systems - End of Unit Exam
Full 55-mark printable exam paper covering all five lessons: Von Neumann model, CPU components, performance factors, memory hierarchy and storage technologies.
What you'll cover
CPU ArchitectureVon Neumann model, components and how data moves around the processor
Performance factorsClock speed, cores, cache - and why faster is not always simple
Memory hierarchyRAM, ROM, cache, and why we need all of them
Storage technologiesHow HDDs, SSDs, optical and flash storage actually work
Tools used in this series
Each lesson links directly to interactive CodeBash tools so you can see the concepts live.
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