Editing Computer data storage (section)

=== Magnetic ===
{{Magnetic storage media}}

[[Magnetic storage]] uses different patterns of [[magnetization]] on a [[magnetically]] coated surface to store information. Magnetic storage is ''non-volatile''. The information is accessed using one or more read/write heads which may contain one or more recording transducers. A read/write head only covers a part of the surface so that the head or medium or both must be moved relative to another in order to access data. In modern computers, magnetic storage will take these forms:

* [[Disk storage|Magnetic disk]];
** [[Floppy disk]], used for off-line storage;
** [[Hard disk drive]], used for secondary storage.
* [[Magnetic-tape data storage|Magnetic tape]], used for tertiary and off-line storage;
* [[Carousel memory]] (magnetic rolls).

In early computers, magnetic storage was also used as:

* Primary storage in a form of [[Drum memory|magnetic memory]], or [[core memory]], [[core rope memory]], [[thin-film memory]] and/or [[twistor memory]];
* Tertiary (e.g. [[NCR CRAM]]) or off line storage in the form of magnetic cards;
* Magnetic tape was then often used for secondary storage.

Magnetic storage does not have a definite limit of rewriting cycles like flash storage and re-writeable optical media, as altering magnetic fields causes no physical wear. Rather, their life span is limited by mechanical parts.<ref>{{cite web |title=Comparing SSD and HDD endurance in the age of QLC SSDs|url=https://www.micron.com/-/media/client/global/documents/products/white-paper/5210_ssd_vs_hdd_endurance_white_paper.pdf |archive-url=https://ghostarchive.org/archive/20221009/https://www.micron.com/-/media/client/global/documents/products/white-paper/5210_ssd_vs_hdd_endurance_white_paper.pdf |archive-date=2022-10-09 |url-status=live|publisher=Micron technology}}</ref><ref>{{cite web|title=Comparing SSD and HDD - A comprehensive comparison of the storage drives|url=https://www.stellarinfo.co.in/kb/ssd-vs-hdd.php |website=www.stellarinfo.co.in|language=en}}</ref>