Databases are saved in file formats, which contain records. At physical level, on some device, there are some actual data which is stored in the electromagnetic format. These storage space gadgets can be broadly categorized into three types

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What is Storage System, Hurry Up!
Databases are saved in file formats, which contain records. At physical level, on some
device, there are some actual data which is stored in the electromagnetic format. These
storage space gadgets can be broadly categorized into three types −
Primary Storage − The storage space that is directly accessible to the CPU comes under
this category.
CPU’s internal storage space (registers), fast memory (cache), and main memory (RAM)
are directly accessible to the CPU, as they are all placed on the motherboard or CPU
chipset.
This storage space is typically very small, very fast, and unstable.
For maintaining the data, this storage requires continous supply of power.
In case of a power failure, all its information is lost.

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storage space.
Secondary Storage − Secondary storage space
used to storedatathrough backup.
This storage includes storage gadgets that are
not a part of the CPU or motherboard, for
example, magnetic disks, optical disks (DVD, CD,
etc.), hard disks, flash drives, and magnetic tapes.
Tertiary Storage − Tertiary storage space is used
for storing large number of data.

3. Memory Hierarchy
A pc has a well-defined hierarchy of storage. A
CPU can access main storage as well as its inbuilt
signs up.
The access time of the main storage is obviously
less than the CPU rate.
To minimize this rate mismatch, cache memory is
introduced. Cache storage provides the fastest
accessibility time and it contains information that
is most frequently accessed by the CPU.

4. Magnetic Disks
Hard disk drives are the most common secondary
storage space gadgets in the current generation of
computers.
Magnetic disk is the name given to it, because
they use the concept of magnetization to store
information.
Hard disk consist of metal disks coated with
magnetizable material. These disks are placed
vertically on a spindle.

5. Redundant Range of Independent Disks
RAID or Redundant Array of Independent Disks,
is a technology to connect several secondary
storage space gadgets and use them as a single
storage space media.
RAID consists of an array of disks in which
several disks are connected together to achieve
different goals.
RAID levels define the use of hard disk arrays.

6. RAID 1
RAID 1 uses mirroring techniques. When
information is sent to a RAID controller, it makes a
copy of the data and then forward it to the array of
disks. RAID stage 1 is also called mirroring and
provides 100% redundancy in case of a failure.
RAID 2
RAID 2 stores Error Correction Code using
Hamming distance for its information,shared on
different disks. Like stage 0, each information bit

7. RAID 4
In this stage, an entire combination of data is
written onto information pushes and then the
equality is produced and saved on a different disk
drive.
Note that stage 3 uses byte-level striping,
whereas stage 4 uses block-level striping. Both
stage 3 and stage 4 require at least three disk for
implementation of RAID.
RAID 5