Topic 3 - Secondary storage

What is the smallest unit of measurement of computer data?

1 bit (0 or 1)

How many bits are in 1 nibble?

four bits

How many bits are in 1 byte?

8 bits

How many nibbles make 1 byte?

two nibbles

How many bytes are in 1 kilobyte (kB)?

1000/1024 bytes

How many kilobytes are in 1 megabyte (MB)?

1000/1024 kilobytes

How many megabytes are in 1 gigabyte (GB)?

1000/1024 megabytes

How many gigabytes are in 1 terabyte (TB)?

1000/1024 gigabytes

How many terabytes are in 1 petabyte (PB)?

1,000 terabytes

Is RAM volatile or non-volatile?

volatile

Is secondary storage volatile or non-volatile?

non-volatile

What can secondary storage be used for in terms of data retention?

permanent storage for data

What internal storage device types exist?

Magnetic storage, Optical storage, Solid state storage

What media does magnetic storage include?

Hard disk drive (HDD), Network Attached Storage, Magnetic tape

What is the main storage device in a computer?

A HDD

What is stacked on a spindle inside a hard disk?

multiple circular disks

How many read/write heads does each disk in a hard drive have?

two read/write heads

In what form is data stored on a hard disk?

binary code

What magnetizes tiny areas on platter surfaces to represent binary values?

The read/write heads

What acts as a network hard drive connected to a network rather than directly to a computer?

Network Attached Storage

Which magnetic storage media is used by large organizations to back up data?

Magnetic tape

What media does optical storage include?

Compact disk (CD), Digital Versatile Disk (DVD), Blu-ray (BD)

What technology do optical storage devices use to read and write data?

lasers

What reads data on an optical disk?

A low-power laser

What writes data onto an optical disk?

a higher-power laser

What patterns on an optical disk reflective surface represent binary data (0s and 1s)?

pits and lands

How many times is data written to a CD-ROM?

written only once

Can data be erased from a CD-Recordable (CD-R)?

Data cannot be erased

Can data be deleted from a CD ReWritable (CD-RW)?

Data can also be deleted

How much data can a single layer Blu-ray disk store?

25GB

How much data can a double layer Blu-ray disk store?

up to 50GB of data

What media does solid state storage include?

Solid state disk (SSD), USB memory sticks, Memory cards/SD cards

Where is data stored directly in solid state media?

onto microchips

Are there moving parts involved in writing or reading data on solid state storage?

no moving parts

What form of flash memory is solid state storage?

non-volatile

What type of memory do solid state devices use to store data indefinitely?

non-volatile random access memory

Why are solid state devices ideal for portable devices?

require little power

What is Cloud Storage?

The online storage of data on remote servers that are maintained by a cloud service provider

When deciding on a storage medium, what does 'Cost' evaluate?

what is the cost per gigabyte (GB)?

When deciding on a storage medium, what does 'Capacity' evaluate?

how much data can the medium hold?

When deciding on a storage medium, what does 'Speed of access' evaluate?

how quickly can data be transferred to and from the medium?

When deciding on a storage medium, what does 'Portability' evaluate?

how portable is the medium?

When deciding on a storage medium, what does 'Durability' evaluate?

how robust is the medium

When deciding on a storage medium, what does 'Reliability' evaluate?

how resilient and long-lasting is the medium?