Why do computers have primary storage (memory)?
To provide fast access to data, instructions and software currently in use by the CPU.
What does primary storage usually consist of?
RAM and ROM.
What does it mean for memory to be volatile?
Its contents are lost when the computer loses power.
What is stored in RAM?
The data and instructions the computer is currently working with.
Is RAM volatile or non-volatile?
Volatile.
What is stored in ROM?
Firmware essential for the computer to boot and operate.
Can ROM be modified during normal operation?
No (False).
Is ROM volatile or non-volatile?
Non-volatile.
Why is virtual memory needed?
When RAM is full but more programs/data need to be loaded.
How does virtual memory work?
It uses part of secondary storage as if it were extra RAM.
What is stored in cache?
Frequently used data and instructions.
Name three types of secondary storage.
Solid-state, optical, magnetic.
How do SSDs store data?
Using electrical circuits that trap electrical charge (no moving parts).
How do optical disks store data?
Using a laser to read data on discs such as CDs or DVDs.
How do magnetic hard disks store data?
Using tiny magnetised regions.
Rank secondary storage by capacity (high → low).
HDD → SSD → Optical.
Rank secondary storage by speed (high → low).
SSD → HDD → Optical.
Rank secondary storage by portability (best → worst).
SSD → Optical → HDD.
Rank secondary storage by durability (most → least).
SSD → HDD → Optical.
Rank secondary storage by reliability (most → least).
SSD → HDD → Optical.
Rank secondary storage by cost per GB (cheapest → most expensive).
HDD → Optical → SSD.
Two uses for HDDs?
Desktop PCs, servers.
Three uses for SSDs?
Laptops, phones, tablets.
Use for optical disks?
Sharing/distributing small volumes of data.
