Editing Disk read-and-write head (section)

===GMR heads===
In 1997 GMR, giant magnetoresistive heads started to replace AMR heads.<ref name=comphist-museum>{{cite journal|author-link1=Christopher H. Bajorek |author=Christopher H. Bajorek |date=November 2014 |title=Magnetoresistive (MR) Heads and the Earliest MR Head-Based Disk Drives: Sawmill and Corsair |journal=Computer History Museum, Mountain View, CA |url=http://www.computerhistory.org/groups/storagesig/media/docs/Magnetoresistive_Heads.pdf |access-date=2015-09-25 |url-status=dead |archive-url=https://web.archive.org/web/20151220202441/http://www.computerhistory.org/groups/storagesig/media/docs/Magnetoresistive_Heads.pdf |archive-date=2015-12-20 }}</ref>

Since the 1990s, a number of studies have been done on the effects of [[colossal magnetoresistance]] (CMR), which may allow for even greater increases in density. But so far it has not led to practical applications because it requires low temperatures and large equipment size.<ref>{{Cite news|url=https://www.abdn.ac.uk/news/5726/|title=Chemists exploring new material with 'next generation' computer hard drive possibilities|date=27 January 2014|work=The University of Aberdeen News}}</ref><ref>{{Cite book|title=Nanoscale Phase Separation and Colossal Magnetoresistance: The Physics of Manganites and Related Compounds|volume=136|last=Dagotto|first=Elbio|publisher=Springer Science & Business Media|date=14 March 2013|isbn=9783662052440|pages=395–396|chapter=Brief Introduction to Giant Magnetoresistance (GMR)|doi=10.1007/978-3-662-05244-0_21|series=Springer Series in Solid-State Sciences}}</ref>