Memory

Question 1

What does primary storage consist of?

Answer 1

• Random Access Memory. (RAM)>
• Read Only Memory (ROM)
• ## Registers and Cache.

Question 2

Why do we need primary storage?

Answer 2

• Holds the data and instructions needed by the CPU whilst the computer is running.
• Data can be accessed much more quickly from primary storage then secondary storage.

Question 3

What is ROM?

Answer 3

• Small piece of read only memory located on the motherboard.
• Non-Volatile.
• Contains the very first instructions for the computer (bootstrap).
• Programmes may be stored in ROM in embedded system.

Question 4

What is RAM?

Answer 4

• Temporary storage of data and instructions.
• Holds information being executed by the processor.
• Volatile.
• Much faster than a hard disk.
• Holds the operating system.
• Larger in comparison to ROM.

Question 5

What is virtual memory?

Answer 5

• VM is used when there is not enough physical RAM to store the open programmes.
• Virtual memory is held on the hard drive.
• Programmes are transferred out of virtual memory from the RAM when they are currently not being executed.
• Programmes are transferred back into RAm from Virtual memory when they are needed to be executed.

Question 6

Why is secondary storage needed?

Answer 6

• Needed because ROM is read only and RAM is volatile.
• Secondary Storage is needed for:
• Storage of programmes + Data when power is turned off.
• Backup of data files.
• Archive of data files.

Question 7

Common Types of Storage:

Answer 7

• Optical.
• Magnetic.
• Solid-State.

Question 8

Optical Storage:

Answer 8

(CD-R, DVD,

• Low capacity compared to other types of storage.
• Slow to access data.
• Thin, Light weight and portable.

Question 9

Optical Storage:

Answer 9

(CD-R, DVD,

• Low capacity compared to other types of storage.
• Slow to access data.
• Thin, Light weight and portable.

Question 10

Solid State Memory: USB memory sticks, solid state drives.

Answer 10

• Medium storage capacity.
• Very quick to access data.
• No moving parts.
• ## Reliable.
• Disadvantages:
• Limited number of read/write cycles.
• Expensive compared to other types of storage.

Question 11

Magnetic: (Hard Disk Drive, Tape).

Answer 11

• High storage compacity.
• Quick to access data.
• Has moving parts however that may eventually fail.
• Hard disks perform better when they are defragmented.

Question 12

What factors needs to be taken account?

Answer 12

• Capacity.
• Speed.
• Portability.
• Durability.
• Reliability.
• Cost.

Question 13

When should optical be used?

Answer 13

• read only data distribution on a large scale.
  -r a small capacity solution.
  -

Question 14

When should magnetic be used?

Answer 14

• When high data capacity.
• Fast Access to data.
• Low cost solutions.
• Suitable for cloud storage on server farms.

Question 15

When should solid state storage be used?

Answer 15

• Suitable for low power, small embedded systems.

- rRugged applications