Secondary Storage

Question 1

What are some examples of primary storage?

Answer 1

ROM
RAM
cache&registers

Question 2

Why is secondary storage sometimes needed?

Answer 2

Because with primary, you can either only read data and cannot change it (ROM) or it is volatile (RAM)

Question 3

What is secondary storage needed for?

Answer 3

• Storage of programs and data when the power is off
• semi-permanent storage of data that can change
• backup of data
• archive data

Question 4

What are the three common types of secondary storage?

Answer 4

• solid state
• optical
• magnetic

Question 5

What is the “drive”?

Answer 5

The device that reads and writes the data from the secondary storage

Question 6

What is the “media”?

Answer 6

Where the data is actually stored

Question 7

What does optical storage include?

Answer 7

-optical drive
-choice of media (CD-R, CD-RW, DVD-R, DVD-RW, Blu-ray)
CD=compact disk
DVD= digital versatile disk

Question 8

How do optical drives work?

Answer 8

Use reflected light to determine the binary digits stored.

Question 9

How do magnetic disks work?

Answer 9

Use the polarity of magnetised compounds as binary digits.

Question 10

What are some examples of solid state storage?

Answer 10

memory stick
flash memory
solid state drive

Question 11

How does solid state disks work?

Answer 11

Use trapped electrons to vary the charge in a nand flash cell made up of metal oxide semi-conductor field effect transistors.

Question 12

advantages and disadvantages of hard disks

Answer 12

ADVANTAGES
- high capacity
- access data ~reasonably~ quickly
- tend to be long lasting
- cheap for a bite to bite comparison
DISADVANTAGES
- can be bulky, don't drop it
- will eventually fail

Question 13

advantages and disadvantages of magnetic tape

Answer 13

ADV
- high capacity
-highly portable
-reasonably robust
-fairly reliable
-cheap solution to a high volume backup
DISADV
- slow to access data
-can be damaged-be careful

Question 14

advantages and disadvantages of CD-R/RW and DVD-R/RW and Blu-Ray

Answer 14

ADV
- very portable
-pretty durable
-data can be stored very quickly-ideal for mass production
DISADV
-CD only store 640mb data
-DVD only stores 4.7gb data
Blu-Ray only stores 25gb data
- slow to access data
-dirt/scratches make it unreadable

Question 15

pros and cons of flash memory

Answer 15

ADV

• reasonable capacity
• very rugged
• no moving parts
• very reliable

DISADV

• will fail-limited no. read, write cycles
• quite expensive (bite for bite comparison)

Question 16

pros and cons for SSD

Answer 16

ADV
- much faster than magnetic hard disks
-no moving parts
-any bit of data can be accessed immediately
DISADV
-expensive

Question 17

What storage system would be ideal for a helmet mounted camera?

Answer 17

SSD

• can quickly move data on and off media
• portable
• durable
• reliable

Question 18

What would be ideal for a desktop computer in an office?

Answer 18

hard disk (&SSD)

• high storage capacity
• fast access
• portability and durability not big problems
• cheap

Question 19

What is cloud storage?

Answer 19

remote servers that store data that can be accessed over the internet
(typically use magnetic hard drives, SSDs becoming more popular)

Question 20

Advantages of cloud storage?

Answer 20

1. access files anywhere, anytime
2. automatic back-up is possible
3. more space on your own advice
4. collaborate easily

Question 21

Disadvantages of cloud storage?

Answer 21

1. can be costly

2. no access to files if no internet connection