Disk storage involves recording data on rotating disks through electronic, magnetic, optical, or mechanical methods. Basic units of data storage are bits, bytes, kilobytes, megabytes, gigabytes, and terabytes. Memory is volatile storage that is directly accessible by the CPU, while disk storage is non-volatile storage that is not directly accessible and requires reading from and writing to through memory. Common disk storage devices include hard disk drives, optical discs, magnetic tapes, floppy disks, portable hard disks, solid state drives, and cloud storage. Formatting prepares a storage device for initial use and may create file systems.

1. Disk
Storage
Presented by :
Md : Jayed Hossain Jibon
B.sc in SWE
Daffodil International University

2. What is disk storage
device?
Disk storage is a general category of storage mechanisms where
data are recorded by various electronic, magnetic, optical, or
mechanical changes to a surface layer of one or more rotating
disks.
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3. Bit : Computer works with binary digits. 0’s and 1’s
Byte : A collection of eight bits is called byte
Kilobyte : A kilobyte consists of 1024 bytes. It is denoted by KB.
Megabyte : A megabyte consists of 1024 kilobytes. It is denoted by MB.
Gigabyte : A gigabyte consists of 1024 megabytes. It is denoted by GB.
Terabyte : A terabyte consists of 1024 gigabytes. It is denoted by TB.
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Basic unit of data storage
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What is the difference between memory
and disk storage?
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Memory / storages categories
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8. Write a file to
Disk
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1. Place an empty disc into your CD/DVD writable drive.
2. In the Blank CD/DVD-R Disc window that appears,
select CD/DVD Creator and click OK. ...
3. In the Disc Name field, type a name for the disc.
4. Drag or copy the desired files into the window.
5. Click Write to Disc.
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9. Formatting
Disk
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Disk formatting is the process of preparing a data storage
device such as a hard disk drive, solid-state drive,
floppy disk or USB flash drive for initial use. In some
cases, the formatting operation may also create one or
more new file systems.
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10. Types of disk storage
devices
1. Hard disk drive
2. Optical storage devices
3. Magnetic tape drive
4. Floppy disk
5. Portable hard disk
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11. Modern storage
devices
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Modern storage devices examples
1. Solid State Drives (SSD)
2. Memory Chips
3. USB drives
4. Cloud Storages
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12. Advantages of disk
storage devices
1. Control over the data
2. The data can be easily manipulated when stored
3. Cost per unit of data is lower
4. data loss on power failure or system crash
5. Physical failure of the storage device
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13. Disadvantage of disk
storage devices
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1. Not very strong and - easy to damage
2. Quit slow to access
3. Small Storage Capacity
4. Consumes a lot of power
5. Data error is frequent
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