In computing, a data storage device—as the name implies—is a device for storing data. It usually refers to permanent (non-volatile) storage, that is, the data will remain stored when power is removed from the device; unlike semiconductor RAM. Recording can be done mechanically, magnetically, or optically.

A typical way to classify data storage media is to consider its shape and type of movement (or non-movement) relative to the read/write device(s) of the storage apparatus. The following is a list of storage media, roughly sorted descending from modern to older/archaic media.

• Flash memory/memory card (solid state semiconductor memory)
  • CompactFlash I and II
  • SONY Memory stick (Std/Duo/Pro/MagicGate versions)
  • Secure Digital
  • MMC
  • SmartMedia
  • xD
  • USB Keydrive (a.k.a. "thumb drive")
• Magnetic bubble memory
• Disk storage (flat, round, circularly-spinning object)
  • Optical disc such as CD-ROM, CD-R, CD-RW, DVD, DVD-R, DVD-RW, DVD+R, DVD+RW, DVD-RAM, Blu-ray, Minidisc
  • Hard disk (magnetic)
  • Holographic
  • Floppy disk, ZIP disk (removable) (magnetic)
  • Gramophone record (used for distributing some 1980s home computer programs) (mechanical)
• Tape storage (long, thin, flexible, linearly moving bands)
  • Magnetic tape (a tape passing one or more read/write/erase heads)
  • Paper tape (mechanical)
• Paper card storage
  • Punched card (mechanical)

As of 2003 it is expected that in the future, miniaturization might lead to the invention of devices that store bits on a single atom each (Bekenstein, 2003).

See also: computer storage

References

• Bekenstein, Jacob D. (2003, August). Information in the holographic universe. Scientific American.
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