Grade 11 · Theory
Memory as part of a computer system
Hardware · about 3 min
Visual overview: Memory as part of a computer system1 MIN READ
2 study sections · pause after each one and recall the key ideaMemory is the computer's working space. Understanding the memory hierarchy — registers, cache, RAM, storage — explains most performance behaviour.
Key points- RAM holds running programs and their data; it is volatile (cleared at power-off).
- More RAM lets more programs run without swapping to disk.
- Virtual memory: the OS uses disk space as overflow "RAM" — it works, but slowly.
- ROM holds permanent startup firmware.
- Hierarchy trade-off: the faster the memory, the smaller and more expensive it is.
- Volatile — loses contents without power (RAM); non-volatile keeps them (ROM, SSD).
- Virtual memory/paging — using storage to extend RAM.
EXAM TIP
describe what happens when RAM is full (thrashing/swapping) and the practical fix (add RAM, close programs).