BIMS – L1 – QF1 – Introduction to information technology and information systems

Define and explain key features of primary storage (internal memory).

Question

Define and explain the key features of the following types of storage device:

(a) Primary storage (internal memory)

(b) Secondary storage (external memory)

(d) Off-line storage

Answer

(a). Internal temporary store directly accessible by the CPU that allows it to process data.
Volatile by nature as it is erased when power is turned off.
Much smaller than secondary or tertiary storage but much quicker to access (as it has no mechanical parts).
Examples include RAM and ROM plus the CPU’s cache memory (temporary store of instructions repeatedly required to run programs – typically up to 2MB (megabytes) in size).

Internal temporary store directly accessible by the CPU that allows it to process data.
Volatile by nature as it is erased when power is turned off.
Much smaller than secondary or tertiary storage but much quicker to access (as it has no mechanical parts).
Examples include RAM and ROM plus the CPU’s cache memory (temporary store of instructions repeatedly required to run programs – typically up to 2MB (megabytes) in size).

(b). Secondary storage differs from primary storage in that it is not directly accessible by the CPU.
Secondary storage is used for data not currently being processed but which may need to be accessed at a later stage, for example the operating system, documents, music files and emails.
Non-volatile as data remains intact even when powered off.
Located further from the CPU than primary storage (and not directly accessible by the CPU). Therefore takes longer to access. However, is much larger than primary storage.
A computer’s largest secondary storage location is typically its hard disk drive (also called hard drive), the capacity of which would typically fall between 40GB (gigabytes) to 2 TB (terabytes). Other examples include:

Flash memory (USB flash drives or keys)
Floppy disks
CD
DVD
Blu-ray drive
Magnetic tape
Cloud drive

(c). Tertiary storage is not as commonly recognisable as primary or secondary storage by most computer consumers as they may never encounter it.

Tertiary storage typically involves a robotic mechanism that mounts (inserts) and dismounts removable mass storage media into a storage device.
Often used for archiving rarely accessed information as it is much slower than secondary storage.
Primarily useful for extremely large data stores accessed without human operators.

Tertiary storage is not as commonly recognisable as primary or secondary storage by most computer consumers as they may never encounter it.
Tertiary storage typically involves a robotic mechanism that mounts (inserts) and dismounts removable mass storage media into a storage device.
Often used for archiving rarely accessed information as it is much slower than secondary storage.
Primarily useful for extremely large data stores accessed without human operators.

(d). Off-line storage describes any type of data storage that is not under the control of a processing unit. The medium is typically recorded on a secondary or tertiary storage device which is physically removed or disconnected. Off-line storage therefore needs human intervention to reconnect for subsequent access.

With off-line storage being physically separate from the computer it can be used to increase general information security. For example keeping a copy of all your important files off-line in a separate building.

Off-line storage describes any type of data storage that is not under the control of a processing unit. The medium is typically recorded on a secondary or tertiary storage device which is physically removed or disconnected. Off-line storage therefore needs human intervention to reconnect for subsequent access.
With off-line storage being physically separate from the computer it can be used to increase general information security. For example keeping a copy of all your important files off-line in a separate building.

Tags: Computer Systems, External Memory, Secondary Storage, Storage
Level: Level 1

Topic: Introduction to information technology and information systems

Uploader: Samuel Duah