1.2 Memory and storage (1.2.2 Secondary storage)

Question 1

what is secondary storage

Answer 1

• it is not directly accessible by the CPU
• the types of storage are hard disk drive (HDD) and solid state drive (SDD)
• it is non-volatile

Question 2

what are the different storage methods

Answer 2

• magnetic
• optical
• solid state

Question 3

What is magnetic storage?

Answer 3

• mechanical parts move over the disks surface to read and write data magnetically
• magnetic tape has a greater storage capacity than HDDs
• they are a cheap form of storage compared to solid state drives

Question 4

What is optical storage?

Answer 4

• lasers read and write data using light

- examples are CD-ROM, DVD, Blu-Ray

Question 5

What is solid state?

Answer 5

• data is recorded onto solid memory chips without any moving parts
• they have significantly faster read/write times than HDDs
• uses non-volatile flash memory to store information - NOT A TYPE OF MEMORY

Question 6

advantages of magnetic storage

Answer 6

• cheap
• large storage capacities
• relatively fast read/write speed

Question 7

disadvantages of magnetic storage

Answer 7

lots of mechanical parts, durability is an issue

Question 8

advantages of optical storage

Answer 8

• cheap
• easily portable
• takes up little physical space

Question 9

disadvantage of optical storage

Answer 9

• less storage capacity compared to other types
• easily damaged/ scratched
• slow write speeds

Question 10

advantages of solid state drives

Answer 10

• highly durable
• no moving parts
• very fast read/write speeds

Question 11

disadvantages of solid state drives

Answer 11

• more expensive than magnetic hard disks

- similar storage capacity as magnetic disks

Question 12

Capacity of different storage types

Answer 12

magnetic - very large
optical - low
solid state - very large

Question 13

speed of different storage types

Answer 13

solid state - very fast

magnetic - fast

optical - slow

Question 14

portability of different storage types

Answer 14

magnetic - not very, due to moving parts
optical - portable
solid state - very portable

Question 15

durability of different storage types

Answer 15

magnetic - very durable

optical - easily scratched and data can be damaged

solid state - lower than a hard disk drive

Question 16

reliability of different storage types

Answer 16

magnetic - very reliable
optical - very reliable if not scratched
solid state - very reliable

Question 17

cost of different storage types

Answer 17

magnetic - very low
optical - very low
solid state - more expensive per GB than other technologies

Question 18

why do we need secondary storage

Answer 18

it is non-volatile, meaning it retains its contents without the need for a power supply