DATA STORAGE DEVICES

• A storage device is an integral part of the computer hardware which stores information/data to process the result of any computational work.
• Without a storage device, a computer would not be able to run or even boot up. 
• In other words, we can say that a storage device is hardware that is used for storing, porting, or extracting data files.

TYPES OF DATA STORAGE DEVICES:

• Primary Storage Devices
• Magnetic Storage Devices
• Flash memory Devices
• Optical Storage Devices
• Cloud and Virtual Storage

PRIMARY STORAGE DEVICES:

1. RAM (RANDOM ACCESS MEMORY)

• It is used to store information that is used immediately or we can say that it is a temporary memory. Computers bring the software installed on a hard disk to RAM to process it and to be used by the user.
• With the help of RAM, computers can perform multiple tasks like loading applications, browsing the web, editing a spreadsheet, experiencing the newest game, etc. 
•  It ranges from 1GB – 32GB/64GB depending upon the specifications.

    2. ROM (READ ONLY MEMORY)

•  The data written or stored in these devices are non-volatile, i.e, once the data is stored in the memory cannot be modified or deleted.
•  ROM stores instructions that are used to start a computer. This operation is referred to as bootstrap.
• . ROM chips can only store a few megabytes (MB) of data, which ranges between 4 and 8 MB per ROM chip.

MAGNETIC STORAGE DEVICES:

1. FLOPPY DISK

• It is generally used on a personal computer to store data externally.
• A floppy disk is a round, flat piece of flexible plastic which is coated with magnetic oxide.
• It is encased in square plastic cover that gives protection to the disk.
  
• They are also referred as diskettes.
• The floppy disks are available in two sizes.
  o  5 ¼ inch (1.2 MB)
  o  3 ½ inch (1.44 MB)

    2. HARD DISK

• Hard Disk is a storage device that stores and retrieves data using magnetic storage.
• It is a non-volatile storage device that can be modified or deleted n number of times without any problem.
• It supports the direct access of the data.
• It is a thin magnetic plate which is made of metal and both side coated with magnetic material.
  
• The disk is divided in many tracks & the data is store in both side of the disk.
• The disk drive consists of motor to rotate the disk pack about its axis at a speedof about 5400 revolution per minute.

FLASH MEMORY DEVICES:

1. PEN DRIVE

•  It is also known as a USB flash drive that includes flash memory with an integrated USB interface. 
• We can directly connect these devices to our computers and laptops and read/write data into them in a much faster and more efficient way. 
• It ranges from 1GB to 256GB generally.

    2. MEMORY CARD

•  It is also used to store large amounts of data and is available in different sizes. 
• To run a memory card on a computer you require a separate memory card reader.  
• It is generally used in digital cameras. printers, game consoles, etc.

OPTICAL STORAGE DEVICES:

1. CD (COMPACT DISC)

•  It contains tracks and sectors on its surface to store data.
• It is made up of polycarbonate plastic and is circular in shape. 
• Compact disc is portable storage devices used for storing digital data like recording, storing, and playing video, and audio. 

   2. DVD (DIGITAL VERSATILE DISC)

•  DVDs are circular flat optical discs used to store data.
• Data is recorded on each layer so that the storage capacity is become large.
• It comes in two different sizes one is 4.7GB single-layer discs and another one is 8.5GB double-layer discs. 

   3. BLUE RAY DISK

• Blue-Ray disk is an optical disc storage media format.
• It is mainly used to store high definition video and data.
• The violet coloured laser is used to read and write the data.
• Because of its shorter wavelength more data can be stored than DVD format.
• This Blu-ray technology is used to read a disc from a blue-violet laser due to which the information is stored in greater density with a longer wavelength.
• Its storage capacity is 50 GB.

CLOUD AND VIRTUAL STORAGE

• We can store our files and other stuff in the cloud and the data is stored for as long as we pay for the cloud storage.
• There are many companies that provide cloud services, largely Google, Amazon, Microsoft, etc. 
• We can pay the rent for the amount of space we need and we get multiple benefits out of it. 
• Though it is actually being stored in a physical device located in the data centers of the service provider, the user doesn’t interact with the physical device and its maintenance.
• For example, Amazon Web Services offers AWS S3 as a type of storage where users can store data virtually instead of being stored in physical hard drive devices.