The big idea: RAM empties the moment the power goes off.
Secondary storage is where everything you keep actually lives — it is non-volatile, so your files are still there tomorrow.
Secondary storage is the bottom rung: biggest, slowest to reach, and the only one that keeps its data.
Interactive diagram
Explore the labelled diagram, charts and maps for this topic in full study mode.
Why it is slow and that is fine: It holds far more than RAM, and reaching it takes far longer.
That is an acceptable trade because a file only needs loading once — after that it works in RAM.
Free preview
This is the free notes preview
You're reading the free notes. Aimnova Pro unlocks the full study experience — and you can try it with your first topic free to keep:
- FlashcardsLock in vocabulary and key terms with spaced repetition.
- Practice questionsAnswer exam-style questions and get instant AI marking.
- Mock exams & past-paper vaultSit full mocks and see exactly how examiners award marks.
- Personalised study planA daily plan built around your exam date and weak areas.
Internal drives are fitted inside the computer and hold the operating system, programs and files.
SSD — solid state drive
- No moving parts — stores charge in flash memory
- Much faster to read and write
- Survives being knocked; quiet; uses less power
- Costs more per gigabyte
HDD — hard disk drive
- A spinning magnetic disk with a moving read head
- Slower, because the head must physically move
- Damaged more easily if dropped while running
- Much cheaper per gigabyte, so larger for the money
And a third, in small devices: eMMC is flash storage soldered straight onto the board of phones, tablets and cheap laptops. Compact and cheap, but slower than a proper SSD and not replaceable.
Memorize terms 3x faster
Smart flashcards show you cards right before you forget them. Perfect for definitions and key concepts.
External SSD or HDD
The same drives in a case with a cable. Large capacity, moved between machines.
Backups and carrying large files
Flash drive · memory card
Small flash storage. Cards go in cameras and phones; flash drives plug into a USB port.
Small amounts, carried easily
Optical — CD, DVD, Blu-ray
Data read by laser from a plastic disc. Cheap to mass-produce and long-lasting.
Distributing the same content to many people
NAS
Network attached storage: drives on the network that everyone can reach at once.
A household or office sharing files
Answer the scenario, not the list: Questions give you a situation and ask which storage suits it. The marks are in matching the choice to capacity, speed, portability, cost or how many people need it — not in naming the most modern option.
How this is tested — you are given a SCENARIO and must justify a choice from capacity, speed, portability, cost or sharing. It comes up two ways:
Paper 1 Section A
- Describe internal and external secondary storage, 2-4 marks
- Compare an SSD with an HDD
- Recommend storage for a stated situation
Paper 1 Section B — case study
- Choose storage for the case study's organisation
- Justify it against how that organisation works
The classic trap: Recommending an SSD every time because it is fastest. If the scenario is years of backups on a tight budget, the cheaper HDD is the better answer — and saying why earns the mark.
A school is choosing between a solid state drive and a hard disk drive for the computers in a library. Compare the two and recommend one, justifying your choice.
Model answer plan
See the mark-by-mark plan — for / against / judgement, with marking guidance — in study mode.