Hard disk drive
Electro-mechanical magnetic storage device with rotating platters and moving heads.
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A hard disk drive is an electro-mechanical device that stores digital data magnetically on rotating platters.[1] Data is read and written by magnetic heads on a moving actuator arm, allowing random access to any block.[1] HDDs are non-volatile, retaining data when powered off, and are typically housed in a small rectangular box.[2]
How it changed
It stored 3.75 megabytes on 52 disks and was about the size of two large refrigerators.[3] In the 2000s and 2010s, NAND flash began replacing HDDs in portable and high-performance applications.[4] IBM's 1301 disk storage unit, announced in 1961, employed a comb of 48 heads that all moved together horizontally.[5][6] IBM introduced the swinging arm actuator in 1974; this design was eventually adopted for all HDDs starting in the 1980s and remained universal for over 50 years.[7]
Manufacturing plants were damaged by the 2011 Thailand floods, which adversely affected hard disk drive costs from 2011 through 2013.[8]
What the maker and period sources say
A 2012 Ars Technica article noted that hard disk drives were once required to boot Windows or OS X effectively.[9] The same source stated that the original iPod contained a 1.8-inch Toshiba hard disk drive providing 5 GB of storage.[9] Flash was always a better choice for portable devices due to lower power consumption and vibration insensitivity.[9] The 2007 iPhone used NAND flash, quickly ending the future of microdrives in mobile devices.[9]
A 2012 Objective Analysis report noted that 400 exabytes of HDDs shipped in 2011.[10]
References
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: Arpaci-Dusseau, "Operating Systems: Three Easy Pieces, Chapter: Hard Disk Drives", Arpaci-Dusseau Books, 2014 (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: Patterson, "Computer Organization and Design: The Hardware/Software Interface", Elsevier, 1971, p. 23; Domingo, "SSD vs. HDD: What's the Difference?", PC Magazine UK; Mustafa, "2016 International Conference on Embedded Computer Systems: Architectures, Modeling and Simulation (SAMOS)", IEEE, 2016, p. 164–171 (we also read that source) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: "Comment: Time Capsule, 1956 Hard Disk", July 2014; "IBM Archives: IBM 350 disk storage unit", IBM, January 23, 2003; "IBM 650 RAMAC Manual of Operations", June 1, 1957, p. 17; "IBM Reference Manual 7070 Data Processing System", January 1960; "Reference Manual IBM 1401 Data Processing System", April 1962, p. 63 (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: Alcorn, "Need A 100TB SSD? Nimbus Data Has You Covered With The ExaDrive DC100", Tomshardware.com, March 19, 2018; Mott, "Seagate Wants to Ship 100TB HDDs by 2025", November 7, 2018; Mellor, "How long before SSDs replace nearline disk drives?", September 23, 2019 (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: "IBM Archives: IBM 1301 disk storage unit", ibm.com, January 23, 2003 (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: "DiskPlatter-1301" (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: "Design of a Swinging Arm Actuator for a disk file" J. S. HEATH IBM J. RES. DEVELOP. July 1976; US 3,849,800 Magnetic disk apparatus. Cuzner, Dodman, Heath, & Rigbey (original not read by us) en.wikipedia.org
- Wikipedia, "Hard disk drive" (CC BY-SA 4.0), which cites: "Farming hard drives: how Backblaze weathered the Thailand drive crisis", Blaze, 2013 (original not read by us) en.wikipedia.org
- Hutchinson, Lee. (June 25, 2012) How SSDs conquered mobile devices and modern OSes . Ars Technica. Retrieved January 7, 2013.. facts only, no text reused. arstechnica.com
- Handy, "For the Lack of a Fab...", Objective Analysis, July 31, 2012. facts only, no text reused. thessdguy.com
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Hard disk drive (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.
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Sources
Compiled from Wikipedia and the sources listed below. Text from Wikipedia is available under CC BY-SA 4.0; this entry is adapted from it.
- Wikipedia: Hard disk drive (CC BY-SA 4.0).
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