Secondary Storage

Question 1

Drive

Answer 1

A device that reads and writes data from secondary storage

Question 2

3 types of optical storage

Answer 2

CD
DVD
Blu-ray

Question 3

Secondary storage and Primary Storage differences

Answer 3

Secondary storage is non-volatile whilst Primary is volatile

Secondary storage is not directly accessed by the CPU whilst Primary storage is directly accessed by the CPU.

Secondary storage typically have have more memory capacity than Primary storage.

Question 4

How is data read and written in optical storage?

Answer 4

Data is written with a laser burning “pits” and “lands” into the disk. These reflect light differently which is how it is interpreted as binary when reading data. When reading the disk, it spins and a light is reflected off of the surface and the reflections are then interpreted as data.

Question 5

Optical storage advantages

Answer 5

• Good portability
• Cheap

Question 6

How is data read and written in magnetic storage?

Answer 6

Magnetic storage has read and write heads which contain electromagnets. These electromagnets magnetize or demagnetize parts of the surface to represent binary. The data is read with the read head.

Question 7

Optical storage disadvantages

Answer 7

• Doesn’t have a large memory capacity
• Can be scratched easily which makes data inaccurate

Question 8

Magnetic storage advantages

Answer 8

• Large memory capacity
• Cheap per unit of storage

Question 9

Magnetic storage disadvantages

Answer 9

• Can create noise
• Data can be erased by nearby magnets
• High power consumption

Question 10

How is data read and written in solid-state storage?

Answer 10

Solid state storage works by controlling the movement of electrons within NAND or NOR chips. The data is stored as 1s and 0s in millions of transistors within the chip.

Question 11

Solid State storage advantages

Answer 11

• Does not make any noise because no moving parts
• Durable and not affected by physical shock
• Fast access times

Question 12

Solid State storage disadvantages

Answer 12

• Expensive
• Limited read/write cycles

Question 13

Cloud storage

Answer 13

This is when data is stored remotely in server farms or data warehouses

Question 14

Cloud storage advantages

Answer 14

• Can access data anywhere on any device

Question 15

Cloud storage disadvantages

Answer 15

• Cannot access without internet
• Susceptible to cybercrime
• Can be expensive

Question 16

Virtual memory why it is used

Answer 16

When RAM is too full there need to be some way for the CPU to execute instructions that are not currently available in RAM

Question 17

Virtual memory process

Answer 17

• An area of memory in secondary storage is found
• Unused and inactive instructions in RAM are moved to that area in secondary storage
• Pages of required instructions are moved from secondary storage into the RAM
• The CPU can now access the instructions it needs
• Once complete, the instructions can be moved back into the RAM from secondary storage