Storage devices and Media

Question 1

Define Backing up of Data

Answer 1

Backing up refers to copying files or data into a different medium in case of damage or loss of original copy.

Question 2

Why do we back up data?

Answer 2

To safeguard against loss of data.
To safeguard against damages caused by hackers.
In case files need to be sent elsewhere, to protect the original format of files.

Question 3

How does Backing Storage Media saves the data

Answer 3

Holds data magnetically.
The surface area of the media is magnetised so that it can hold bits of data.
The device that reads media can also read the bits held on the surface area

Question 4

What are the uses of Magnetic tape drives

Answer 4

used in applications where batch processing is used.
used as a backup media where vast amounts of data need to be stored.
used in long-term archiving of data, they have huge data storage capacities and are known to be very stable.

Question 5

Advantages and Disadvantages of Magnetic tape drives

Answer 5

Advantages:

They are generally less expensive than hard disk drives.
It is a very robust technology.
They have a huge data storage capacity.
The data transfer rate is fast.
Disadvantages:

Prolonged data access times (uses serial access).
When updating, another tape is needed to store the final updated version.
They are affected by magnetic fields, a strong field can corrupt data stored on the tape.

Question 6

What are the uses of Fixed Hard Disks/Drives

Answer 6

To store the OS, systems software and working data/files.
Storing applications files.
Used in real-time systems and in online systems.
Used in file servers for computer networks.

Question 7

Advantages and Disadvantages of Fixed Hard disks/drives

Answer 7

Advantages:

They have a very fast data transfer rate and fast access times to data.
They have a very large memory capacity.
Disadvantages:

It can be fairly easily damaged.
They have many moving parts which affect overall reliability.
Their read/write operation can be quite noisy when compared to solid-state drives

Question 8

Advantages and Disadvantages of Portable Hard disks drives

Answer 8

Advantages:

Data access time and data transfer rate are very fast.
It has a very large memory capacity.
It can be used as a method of transferring information between computers.
Disadvantages:

They can be easily damaged if user accidentally drops it or doesn’t correctly shut down the drive after use.
The data transfer rate is not as fast as for fixed hard disk drives.

Question 9

How does Optical Media and Optical storage device stores the data

Answer 9

Holds data by burning ‘dots’ onto the surface with a high-powered laser.
The data that reads the media can read the data by shining a lower-powered laser over the dots.

Question 10

What are the uses of CD-R/DVD-R

Answer 10

Home recordings of music and (CD-R) and films (CD-R).
Used to store data to be kept for later use to be transferred to another computer.

Question 11

Advantages and Disadvantages of CD-R/DVD-R

Answer 11

Advantages:

Cheaper medium than RW disks.
Once burned (and finalised), they behave like a ROM.
Disadvantages:

It can only be recorded once; if an error occurs, then the disk has to be thrown away.
Not all CD/DVD players can read CD-R/DVD-R.

Question 12

What are the uses of CD-RW/DVD-RW

Answer 12

Used to record television programs which can be recorded over, time and time again.
Used in CCTV systems.
It can be used as a backup device for files and data.

Question 13

Advantages and Disadvantages of CD-RW/DVD-RW

Answer 13

Advantages:

It can be written over many times.
You can use different file formats each time it is used.
It is not as wasteful as the R format because the files/data can be added later.
Disadvantages:

It can be relatively expensive media.
Possible to accidentally overwrite data.

Question 14

What are the uses of CD-ROM/DVD-ROM

Answer 14

These are read-only memory (ROM), which means they can’t be written over and can only be read. Permanent storage method.
CD-ROM is used to store music files and to store software, computer games and reference software.
DVD-ROM has much larger storage and is used to store films.
Used in applications where there is a real need to prevent deletion or overwriting of important data.

Question 15

Advantages and Disadvantages of a CD-ROM/DVD-ROM

Answer 15

Advantages:

They are less expensive than hard disk drive systems.
They are very portable as they are small and light.
Data stored on them is read-only, so it cannot be accidentally overwritten.
Disadvantages:

Hold far less data than hard disk drives or memory sticks.
Very slow data transfer rate and data access times, as compared to hard disk drives.
You cannot add your own files to the disks because they are both read-only.

Question 16

What is the difference between blue ray discs and DVD

Answer 16

The main differences between DVD and Blu-ray are:

Blu-ray uses a blue laser rather than a red laser. (The wavelength of blue light is 405nm, much smaller than the 650nm red laser) This makes pits and lands much smaller, so they store five times more data than DVDs.
Blu-ray disks automatically come with a secure encryption system, which helps to prevent piracy and copyright infringement.
The data transfer rate for a DVD is 10 Mbps, and for a Blu-ray disc, it is 36 Mbps.

Question 17

What are the uses of Blue ray Discs

Answer 17

Home video consoles.
Storing and playing back movies.
Computers can use this technology for data storage or backing hard drives.
Camcorders can use this media to store movies.

Question 18

Advantages and Disadvantages of Blue ray discs

Answer 18

Advantages:

Very large storage capacity.
Very fast data transfer rate.
The data access speed is also greater than with other optical media.
Blu-ray discs automatically come with a secure encryption system.
Disadvantages:

Relatively expensive discs.
Encryption problems when used to store videos.
The introduction of HD (high definition) DVD players has reduced the advantages of using Blu-ray technology.

Question 19

How does Solid state drive save the data

Answer 19

Holds data on devices that don’t have any moving devices.

Question 20

What is the use of Solid State Drive

Answer 20

storage device to store files, applications, OSs, and so on.

Question 21

Advantages of and disadvantages of solid state drive

Answer 21

Advantages:

They are more reliable as they have no moving parts.
They are considerably lighter, and suitable for laptops.
They do not have to ‘get up to speed’ before they work correctly.
They have lower power consumption.
They run much cooler than HDDs.
Because of no moving parts, they are very thin.
SSD data access time is only 0.1 milliseconds compared to 10 milliseconds for HDD.
Data transfer speed for SSDs is also much faster than for HDDs.
Disadvantages:

SSD endurance - SSDs are conservatively rated at only 20GB write operations per day over a three-year period.
More expensive than magnetic hard disks.
Smaller storage capacity than magnetic hard disks

Question 22

What are the uses of Pen Drive (Memory sticks)

Answer 22

Transporting files between computers or using as a backing store.
Used as a security device to prevent software piracy (known as a dongle).

Question 23

Advantages and Disadvantages of Pen drives

Answer 23

Advantages:

Very compact and portable media.
Very robust.
Does not need additional software to work on most computers.
They are not affected by magnetic fields.
Disadvantages:

Cannot write protect the data/files by making it ‘read-only’.
Easy to lose (due to the small physical size).
The user needs to be very careful when removing a memory stick from a computer - incorrect removal will corrupt the data on the memory stick and make it useless

Question 24

What are the different types of Flash Memory Cards

Answer 24

Different types of memory cards:

» SD cards (secure digital card)

» XD cards (extreme digital card)

» CFast card (compact, fast card).

Question 25

What are the uses of Flash Memory Cards

Answer 25

Storing photos on digital cameras.
Used as mobile phone memory cards.
Used in MP3 players to store music files.
Used as a backing store in hand-held computer devices.

Question 26

Advantages and Disadvantages of Flash memory cards

Answer 26

Advantages:

Very compact.
Because of no moving parts, they are very durable.
They can hold large amounts of data.
Compact cameras and smartphones can read and write memory cards, allowing the user to transport extensive collections of photographs, songs etc.
Disadvantages:

Expensive per gigabyte of memory when compared to HDDs.
Have a lower storage capacity than hard disks.
Have a finite life regarding the number of times they can be read from or written to.
Memory cards, specifically the micro SD card, are the smallest storage devices available, making them more likely to be lost, stolen or damaged.
Users must often purchase a card reader or USB converter to view the data.