1.3 Storage

Question 1

What is secondary storage?

Answer 1

Long term storage of data, files, software, OS (operating system).

Question 2

Why do we need to store data and files etc…?

Answer 2

• To access it again later
• To use software
• To interact with the computer

Question 3

•What would happen without secondary storage?

Answer 3

• Software would need to be installed each time we use it

* You couldn’t save any files, data, images, videos etc.

Question 4

What’s optical storage?

Answer 4

•A laser light creates marks in a pattern on the disk
•A laser light detects where the marks are and translates this into a readable format (pits to represent 1/0)
E.g. Blue ray, DVD rom, cd rom

Question 5

What’s magnetic storage?

Answer 5

•Read/write move across the medium and change how magnetised that part of the medium is
•E.g. one level of magnetism will be a 1, a second will be a 0
E.g. Hard disc drive, tape drive

Question 6

What’s solid state memory?

Answer 6

•This is made of transistors (switches)
•The state of the switches determine if a 1, or 0 is stored
E.g. solid state drive, sd card, USB memory stick

Question 7

What are characteristics of storage?

Answer 7

• Capacity-how much data can it store?
• Speed-how fast can it access the data?
• Portability-how easy is it to move it from one place to another
• Durability-how well does it last e.g. if it is dropped
• Reliability-how consistently does it perform
• Cost-how much does it cost per KB, MB or GB?

Question 8

Which of the 3 secondary storage media has the best capacity?

Answer 8

1 Magnetic
2 solid state
3 optical

Question 9

Which of the 3 secondary storage media has the best speed?

Answer 9

1 solid state
2 magnetic
3 optical

Question 10

Which of the 3 secondary storage media has the best portability?

Answer 10

1 solid state
2 optical
3 magnetic

Question 11

Which of the 3 secondary storage media has the best durability?

Answer 11

1 magnetic
2 solid state
3 optical

Question 12

Which of the 3 secondary storage media has the best reliability?

Answer 12

1 solid state
2 magnetic
3 optical

Question 13

Which of the 3 secondary storage media has the best cost?

Answer 13

1 magnetic and optical

2 solid state

Question 14

Why is a secondary storage device needed in most computer systems?

Answer 14

To store software and files because otherwise software would have to be re downloaded onto the computer system every time you’d turn it on

Question 15

What are two things which would be stored in ram?

Answer 15

• file of the current document

- instructions for programs which are currently in use

Question 16

Identify three common storage technologies someone can use:

Answer 16

Magnetic storage
Optical storage
Solid state

Question 17

What are the 6 main characteristics of storage?

Answer 17

• capacity
• speed
• portability
• durability
• reliability
• cost

Question 18

What’s the data capacity calculation for a text file?

Answer 18

1 byte = 1 character

number of bytes * 1.1

Question 19

What’s the data capacity calculation for a database?

Answer 19

Text = 1 byte per character
Integer/Real = 4/8 bytes
Boolean = 1 byte
Date = 8 bytes
-work out how many bytes in a record
-multiply the number of bytes in one record by the total number of records
-the times that answer by 1.1

Question 20

What’s the data capacity calculation for images?

Answer 20

Number of pixels * number of bytes per pixel * 1.1

Question 21

What’s the data calculation for sound?

Answer 21

BytesPerSample * SamplesPerSecond * channels * duration