This slide will shortly describe what is computer data storage and explain each primary and secondary storage memory.

1. Computer Storages
Classification
MD. REJAUL ISLAM ROYEL
05-08-2017

2. Why is storage needed in a computer?
Without a storage device, a computer can not save or remember any settings or
information and would be considered a dumb terminal.
Although a computer can run with no storage device, it would only be able to
view information unless it was connected to another one that had storage
capabilities.
DEFINATION OF DATA STORAGES:
Computer data storage: Computer data storage is the name for a number
of components of a computer. The main purpose of these components is to
store data.
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3. Storage device Hierarchy
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4. Types Of Storages:-
Mainly two types: 1. Primary Storages
2. Secondary Storages
Primary Storages:( internal memory/ main memory/primary memory)
It is volatile medium that holds memory for short periods of time while a computer is
running.
Example: RAM, CACHE
Secondary Storages:(external memory/secondary memory/ auxiliary storage)
It is a non-volatile medium that holds data until it is deleted or overwritten.
Example: Hard-drive, USB drive, SD card, CD, DVD, Floppy disk, Tape drive ETC.
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5. Examples of computer storage
Magnetic storage devices
Magnetic storage is one of the most common types of storage used with computers and
is the technology that many computer hard drives use.
Floppy diskette
Hard drive
Magnetic strip
Super Disk
Tape cassette
Zip diskette
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6. Optical storage devices
Another common storage is optical storage which uses lasers and
lights as its method of reading and writing data.
Blu-ray disc
CD-ROM disc
CD-R and CD-RW disc
DVD-R, DVD+R and DVD+RW disc
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7. Flash memory devices
Flash memory has started to replace magnetic media as it becomes
cheaper as it is the more efficient and reliable solution.
USB flash drive, jump drive
Memory card
Memory stick
SSD
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8. Conclusion:
Data storage memory are developed small register to large magnetic disk and changed
day by day. There is some reason to have different types of storages.
 Each Memory has a different functionality
Technology are changed
 Large data capable devices are needed.
 Every device should be faster.
and so on…………………
References:
1. Abraham Silberschatz, Greg Gagne, and Peter Baer Galvin, "Operating System Concepts, Ninth Edition
2. https://www.computerhope.com/jargon/s/stordevi.htm [04-08-2017]
3. https://en.wikipedia.org/wiki/Computer_data_storage[04-08-2017]
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9. Any Questions
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