Student of group 961-21 Babadjanov Jamshid English lesson Self studies

Magnetic storage devices
All data are stored using a magnetized medium and data saved in the binary form of 0s and 1s. Magnetic storage is non-volatile storage. Read and write data in magnetic storage devices is very easy so most people like to use magnetic storage devices. Magnetic storage devices have a large capacity for data storage. But the accessing the data is slow. These devices are cheap.
Examples-

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  hard drive
  
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  Floppy disk
  
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  Magnetic tape
  

Optical storage devices

The information is stored at an optical disk in the optical storage devices. This is most useful for huge data storage. Optical storage devices are cheap, lightweight, and easy to transport. As well as these are removable devices. Optical storage devices can be recycled or re-used. One of the disadvantages of optical storage is some traditional PCs are not able to read these disks. An optical device writes data by shining a laser onto the disc. This can only be written once but read many times.
Examples-

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  CD-ROM
  
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  DVD-ROM
  
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  Blur Ray
  
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  HD DVD
  
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  DVD RAM
  
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  CD-R & DVD R
  

Flash memory devices

Flash memory was invented by Dr.Fujio Masuoka at Toshiba in 1980. It is based on EEPROM (Electronically Erasable Programmable Read-Only Memory) Technology. Flash memory devices are non-volatile and we can write and erased programming electrically. Flash memory devices are used for storing data to computers as well as electronic devices such as USB flash drives, MP3 players, and Digital cameras, and solid-state drives. There are two types of flash memory based on using technology

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  NOR flash memory
  
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  NAND Flash memory
  

Flash memory devices are a higher speed of reading and write .these are small in size, portable, consuming less power, low chance to damage, not much cost.
Examples-

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  USB flash drive
  
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  Memory card
  
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  Compact Flash
  
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  MMC
  
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  SDHC Card
  
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  SD card