Computer data storage - Revision history

imported>Xjx921: /* Deployment models */

2026-06-19T15:04:12Z

Deployment models

← Previous revision		Revision as of 15:04, 19 June 2026
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	[[File:Computer storage types.svg\|thumb\|right\|350px\|Various forms of storage, divided according to their distance from the [[central processing unit]]. The fundamental components of a general-purpose computer are [[arithmetic and logic unit]], [[control unit\|control circuitry]], storage space, and [[input/output]] devices. Technology and capacity as in common [[home computer]]s around 2005.]]		[[File:Computer storage types.svg\|thumb\|right\|350px\|Various forms of storage, divided according to their distance from the [[central processing unit]]. The fundamental components of a general-purpose computer are [[arithmetic and logic unit]], [[control unit\|control circuitry]], storage space, and [[input/output]] devices. Technology and capacity as in common [[home computer]]s around 2005.]]

	'''~~Primary storage~~''' (also known as ''~~main~~ memory'', ''internal memory'', or ''~~prime memory~~''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->		'''Main memory''' (also known as '''primary memory''', '''internal memory''' or '''primary storage'''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->

	This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered for a specific [[time]]. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:		This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered for a specific [[time]]. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:
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	* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>		* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>
	* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>		* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>
	** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as well as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.{{~~Citation needed~~\|date=~~September 2025~~}}		** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as well as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.<ref>{{Cite web \|title=What is Amazon VPC? - Amazon Virtual Private Cloud \|url=https://docs.aws.amazon.com/vpc/latest/userguide/what-is-amazon-vpc.html \|access-date=2026-06-19 \|website=docs.aws.amazon.com}}</ref>

	=== Types ===		=== Types ===

imported>Kvng: Reverted 2 edits by ~2026-19215-05 (talk): Unexplained deletion by anon

2026-03-30T15:48:21Z

Reverted 2 edits by ~2026-19215-05 (talk): Unexplained deletion by anon

← Previous revision		Revision as of 15:48, 30 March 2026
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	[[File:DDR2 ram mounted.jpg\|thumb\|1 [[Gibibyte\|GiB]] of [[SDRAM]] mounted in a [[computer]]. An example of ''primary storage''.]]		[[File:DDR2 ram mounted.jpg\|thumb\|1 [[Gibibyte\|GiB]] of [[SDRAM]] mounted in a [[computer]]. An example of ''primary storage''.]]
	[[File:IBM DJNA-351520 Hard Disk A.jpg\|thumb\|15 [[Gigabyte\|GB]] [[Parallel ATA\|PATA]] hard disk drive (HDD) from 1999. When connected to a computer it serves as ''secondary'' storage.]]{{Memory types}}		[[File:IBM DJNA-351520 Hard Disk A.jpg\|thumb\|15 [[Gigabyte\|GB]] [[Parallel ATA\|PATA]] hard disk drive (HDD) from 1999. When connected to a computer it serves as ''secondary'' storage.]]{{Memory types}}

	'''Computer data storage''' or '''digital data storage''' is the retention of [[digital data]] via [[technology]] consisting of [[computer]] components and [[Data storage\|recording media]]. Digital data storage is a core function and fundamental component of computers.<ref name="Patterson">{{Cite book \|title=Computer organization and design: The hardware/software interface \|last1=Patterson \|first1=David A. \|last2=Hennessy \|first2=John L. \|date=2005 \|publisher=[[Morgan Kaufmann Publishers]] \|isbn=1-55860-604-1 \|edition=3rd \|location=[[Amsterdam]] \|oclc=56213091 \|url-access=registration \|url=https://archive.org/details/isbn_9781558606043 }}</ref>{{rp\|15–16}}		'''Computer data storage''' or '''digital data storage''' is the retention of [[digital data]] via [[technology]] consisting of [[computer]] components and [[Data storage\|recording media]]. Digital data storage is a core function and fundamental component of computers.<ref name="Patterson">{{Cite book \|title=Computer organization and design: The hardware/software interface \|last1=Patterson \|first1=David A. \|last2=Hennessy \|first2=John L. \|date=2005 \|publisher=[[Morgan Kaufmann Publishers]] \|isbn=1-55860-604-1 \|edition=3rd \|location=[[Amsterdam]] \|oclc=56213091 \|url-access=registration \|url=https://archive.org/details/isbn_9781558606043 }}</ref>{{rp\|15–16}}

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	'''Primary storage''' (also known as ''main memory'', ''internal memory'', or ''prime memory''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->		'''Primary storage''' (also known as ''main memory'', ''internal memory'', or ''prime memory''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->

	This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:		This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered for a specific [[time]]. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:
	* [[Processor register]]s are the fastest of all forms of data storage, being located inside the processor, with each register typically holding a [[Word (computer architecture)\|word]] of data (often 32 or 64 bits). CPU instructions instruct the [[arithmetic logic unit]] to perform various calculations or other operations on this data.		* [[Processor register]]s are the fastest of all forms of data storage, being located inside the processor, with each register typically holding a [[Word (computer architecture)\|word]] of data (often 32 or 64 bits). CPU instructions instruct the [[arithmetic logic unit]] to perform various calculations or other operations on this data.
	* [[Processor cache]] is an intermediate stage between faster registers and slower main memory, being faster than main memory but with much less capacity. Multi-level [[Memory hierarchy\|hierarchical cache]] setup is also commonly used, such that primary cache is the smallest and fastest, while secondary cache is larger and slower.<!-- Please DO NOT EXPAND above text, especially with L1/L2/etc variants - reader can always click the link. -->		* [[Processor cache]] is an intermediate stage between faster registers and slower main memory, being faster than main memory but with much less capacity. Multi-level [[Memory hierarchy\|hierarchical cache]] setup is also commonly used, such that primary cache is the smallest and fastest, while secondary cache is larger and slower.<!-- Please DO NOT EXPAND above text, especially with L1/L2/etc variants - reader can always click the link. -->
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	===== BIOS =====		===== BIOS =====
	[[Non-volatile memory\|Non-volatile primary storage]] ~~contains~~ a small startup program ([[BIOS]]) is used to [[Bootstrapping#Computing\|bootstrap]] the computer, that is, to read a larger program from non-volatile secondary storage to RAM and start to execute it. A non-volatile technology used for this purpose is called [[read-only memory]] (ROM). Most types of "ROM" are not literally read only but are difficult and slow to write to''.'' Some [[embedded system]]s run programs directly from ROM, because such programs are rarely changed. Standard computers largely do not store many programs in ROM, apart from [[firmware]], and use large capacities of secondary storage.		[[Non-volatile memory\|Non-volatile primary storage]] containing a small startup program ([[BIOS]]) is used to [[Bootstrapping#Computing\|bootstrap]] the computer, that is, to read a larger program from non-volatile secondary storage to RAM and start to execute it. A non-volatile technology used for this purpose is called [[read-only memory]] (ROM). Most types of "ROM" are not literally read only but are difficult and slow to write to''.'' Some [[embedded system]]s run programs directly from ROM, because such programs are rarely changed. Standard computers largely do not store many programs in ROM, apart from [[firmware]], and use large capacities of secondary storage.

	==== Secondary ====<!-- Note that additional direct links point to this section by its name. -->		==== Secondary ====<!-- Note that additional direct links point to this section by its name. -->
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	* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>		* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>
	* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>		* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>
	** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as ~~welll~~ as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.{{Citation needed\|date=September 2025}}		** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as well as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.{{Citation needed\|date=September 2025}}

	=== Types ===		=== Types ===
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	=== Other ===		=== Other ===
	* Vacuum-tube memory:		* Vacuum-tube memory:
	** A [[Williams tube]] used a [[cathode-ray tube]], and a [[Selectron tube]] used a large [[vacuum tube]] to store information.		** A [[Williams tube]] used a [[cathode ray tube]], and a [[Selectron tube]] used a large [[vacuum tube]] to store information.
	* Electro-acoustic memory: [[Delay-line memory]] used [[Longitudinal wave\|sound waves]] in a substance such as [[mercury (element)\|mercury]] to store information.		* Electro-acoustic memory: [[Delay-line memory]] used [[Longitudinal wave\|sound waves]] in a substance such as [[mercury (element)\|mercury]] to store information.
	* [[Optical tape]] is a medium for optical storage, generally consisting of a long and narrow strip of plastic, onto which patterns can be written and from which the patterns can be read back.		* [[Optical tape]] is a medium for optical storage, generally consisting of a long and narrow strip of plastic, onto which patterns can be written and from which the patterns can be read back.
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	{{Basic computer components}}		{{Basic computer components}}
	{{Primary storage technologies}}{{Magnetic storage media}}{{Optical storage media}}{{Paper data storage media}}		{{Primary storage technologies}}
			{{Magnetic storage media}}
			{{Optical storage media}}
			{{Paper data storage media}}

	{{Authority control}}		{{Authority control}}

imported>GKNishimoto: /* Semiconductor */Corrected link to subsection.

2025-12-21T23:04:43Z

Semiconductor: Corrected link to subsection.

← Previous revision		Revision as of 23:04, 21 December 2025
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	** An [[uninterruptible power supply]] (UPS) can be used to give a computer a brief window of time to move information from primary volatile storage into non-volatile storage before the batteries are exhausted. Some systems, for example [[EMC Symmetrix]], have integrated batteries that maintain volatile storage for several minutes.		** An [[uninterruptible power supply]] (UPS) can be used to give a computer a brief window of time to move information from primary volatile storage into non-volatile storage before the batteries are exhausted. Some systems, for example [[EMC Symmetrix]], have integrated batteries that maintain volatile storage for several minutes.
	* [[Immutable object\|Mutability]]		* [[Immutable object\|Mutability]]
	** Storage can be classified into read/write, slow-write/fast-read (e.g. [[CD-RW]], [[Solid-state drive\|SSD]]), [[Write once read many\|write-once/read-many]] or WORM (e.g. [[programmable read-only memory]], [[CD-R]]), read-only storage (e.g. [[Read-only memory#Factory programmed\|mask ROM ICs]], [[CD-ROM]]).		** Storage can be classified into read/write, slow-write/fast-read (e.g. [[CD-RW]], [[Solid-state drive\|SSD]]), [[Write once read many\|write-once/read-many]] or WORM (e.g. [[programmable read-only memory]], [[CD-R]]), read-only storage (e.g. [[Read-only memory#Factory-programmed\|mask ROM ICs]], [[CD-ROM]]).
	* Accessibility		* Accessibility
	** Types of access include [[random access]] and [[sequential access]]. In random access, any location in storage can be accessed at any moment in approximately the same amount of time. In sequential access, the accessing of pieces of information will be in a serial order, one after the other; therefore the time to access a particular piece of information depends upon which piece of information was last accessed.		** Types of access include [[random access]] and [[sequential access]]. In random access, any location in storage can be accessed at any moment in approximately the same amount of time. In sequential access, the accessing of pieces of information will be in a serial order, one after the other; therefore the time to access a particular piece of information depends upon which piece of information was last accessed.
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	{{Main\|Semiconductor memory}}		{{Main\|Semiconductor memory}}

	[[Semiconductor memory]] uses [[semiconductor]]-based [[integrated circuit]] (IC) chips to store information. Data are typically stored in [[metal–oxide–semiconductor]] (MOS) [[memory cell (computing)\|memory cells]]. A semiconductor memory chip may contain millions of memory cells, consisting of tiny [[MOSFET\|MOS field-effect transistors]] (MOSFETs) and/or [[MOSFET#MOS capacitor\|MOS capacitors]]. Both ''volatile'' and ''non-volatile'' forms of semiconductor memory exist, the former using standard MOSFETs and the latter using [[floating-gate MOSFET]]s.		[[Semiconductor memory]] uses [[semiconductor]]-based [[integrated circuit]] (IC) chips to store information. Data are typically stored in [[metal–oxide–semiconductor]] (MOS) [[memory cell (computing)\|memory cells]]. A semiconductor memory chip may contain millions of memory cells, consisting of tiny [[MOSFET\|MOS field-effect transistors]] (MOSFETs) and/or [[MOSFET#MOS capacitor and band diagrams\|MOS capacitors]]. Both ''volatile'' and ''non-volatile'' forms of semiconductor memory exist, the former using standard MOSFETs and the latter using [[floating-gate MOSFET]]s.

	In modern computers, primary storage almost exclusively consists of dynamic volatile semiconductor [[random-access memory]] (RAM), particularly [[dynamic random-access memory]] (DRAM). Since the turn of the century, a type of non-volatile [[floating-gate]] semiconductor memory known as [[flash memory]] has steadily gained share as off-line storage for home computers. Non-volatile semiconductor memory is also used for secondary storage in various advanced electronic devices and specialized computers that are designed for them.		In modern computers, primary storage almost exclusively consists of dynamic volatile semiconductor [[random-access memory]] (RAM), particularly [[dynamic random-access memory]] (DRAM). Since the turn of the century, a type of non-volatile [[floating-gate]] semiconductor memory known as [[flash memory]] has steadily gained share as off-line storage for home computers. Non-volatile semiconductor memory is also used for secondary storage in various advanced electronic devices and specialized computers that are designed for them.

imported>Thenightaway: /* Further reading */

2025-11-12T00:40:09Z

imported>Citation bot: Added date. | Use this bot. Report bugs. | Suggested by Dominic3203 | Category:Computer data storage | #UCB_Category 49/49

2025-06-18T01:42:20Z

Added date. | Use this bot. Report bugs. | Suggested by Dominic3203 | Category:Computer data storage | #UCB_Category 49/49

← Previous revision		Revision as of 01:42, 18 June 2025
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	* Magnetic tape was then often used for secondary storage.		* 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>		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\|date=28 February 2025 \|language=en}}</ref>

	=== Optical ===		=== Optical ===

imported>IrisChronomia: /* Secondary storage */ +wikilink to RAID for concurrent usage of multiple disks

2025-05-22T07:31:16Z

Secondary storage: +wikilink to RAID for concurrent usage of multiple disks

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← Previous revision		Revision as of 15:04, 19 June 2026
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	[[File:Computer storage types.svg\|thumb\|right\|350px\|Various forms of storage, divided according to their distance from the [[central processing unit]]. The fundamental components of a general-purpose computer are [[arithmetic and logic unit]], [[control unit\|control circuitry]], storage space, and [[input/output]] devices. Technology and capacity as in common [[home computer]]s around 2005.]]		[[File:Computer storage types.svg\|thumb\|right\|350px\|Various forms of storage, divided according to their distance from the [[central processing unit]]. The fundamental components of a general-purpose computer are [[arithmetic and logic unit]], [[control unit\|control circuitry]], storage space, and [[input/output]] devices. Technology and capacity as in common [[home computer]]s around 2005.]]

	'''~~Primary storage~~''' (also known as ''~~main~~ memory'', ''internal memory'', or ''~~prime memory~~''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->		'''Main memory''' (also known as '''primary memory''', '''internal memory''' or '''primary storage'''), often referred to simply as ''memory'', is storage directly accessible to the CPU. The CPU continuously reads instructions stored there and executes them as required. Any data actively operated on is also stored there in a uniform manner. Historically, [[History of computing hardware\|early computers]] used [[delay-line memory\|delay lines]], [[Williams tube]]s, or rotating [[drum memory\|magnetic drums]] as primary storage. By 1954, those unreliable methods were mostly replaced by [[magnetic-core memory]]. Core memory remained dominant until the 1970s, when advances in [[integrated circuit]] technology allowed [[semiconductor memory]] to become economically competitive.<!-- Please do not expand above text! Change but no expand any further. Anyone desiring to know more types, let it be [[twistor memory]] or [[bubble memory]] etc, will click the History link. Do not confuse other readers. -->

	This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered for a specific [[time]]. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:		This led to modern [[random-access memory]], which is small-sized, light, and relatively expensive. RAM used for primary storage is [[volatile memory\|volatile]], meaning that it loses the information when not powered for a specific [[time]]. Besides storing opened programs, it serves as [[Page cache\|disk cache]] and [[write buffer]] to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software.<ref>{{cite web\| url = https://www.kernel.org/doc/html/latest/admin-guide/sysctl/vm.html\| title = Documentation for /proc/sys/vm/ — The Linux Kernel documentation}}</ref> Spare memory can be utilized as [[RAM drive]] for temporary high-speed data storage. Besides main large-capacity RAM, there are two more sub-layers of primary storage:
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	* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>		* [[Hybrid cloud storage]] are another cloud security solution, involving storage infrastructure that uses a combination of on-premises storage resources with cloud storage. The on-premises storage is usually managed by the organization, while the public cloud storage provider is responsible for the management and security of the data stored in the cloud.<ref name="jones1">{{cite web \|last=Jones \|first=Margaret \|date=July 2019 \|title=Hybrid Cloud Storage \|url=https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|url-status=live \|archive-url=https://web.archive.org/web/20220621203942/https://www.techtarget.com/searchstorage/definition/hybrid-cloud-storage \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref><ref name="searchstorage12">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref> Using a hybrid model allows data to be ingested in an encrypted format where the key is held within the on-premise infrastructure and can limit access to the use of on-premise [[Cloud storage gateway\|cloud storage gateways]], which may have options to encrypt the data prior to transfer.<ref name="searchstorage1">{{cite web \|last=Barrett \|first=Mike \|date=July 2014 \|title=Definition: cloud storage gateway \|url=https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|url-status=live \|archive-url=https://web.archive.org/web/20220621201806/https://www.techtarget.com/searchstorage/definition/cloud-storage-gateway \|archive-date=2022-06-21 \|access-date=2022-06-22 \|work=SearchStorage}}</ref>
	* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>		* Cloud services are considered "public" when they are delivered over the public Internet.<ref>{{cite web \|last=Rouse \|first=Margaret \|title=What is public cloud? \|url=http://searchcloudcomputing.techtarget.com/definition/public-cloud \|url-status=live \|archive-url=https://web.archive.org/web/20141016022343/http://searchcloudcomputing.techtarget.com/definition/public-cloud \|archive-date=16 October 2014 \|access-date=12 October 2014 \|publisher=Definition from Whatis.com}}</ref>
	** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as well as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.{{~~Citation needed~~\|date=~~September 2025~~}}		** A [[virtual private cloud]] (VPC) is a pool of shared resources within a public cloud that provides a certain level of isolation between the different users using the resources. VPCs achieve user isolation through the allocation of a private IP [[subnet]] and a virtual communication construct (such as a [[VLAN]] or a set of [[encrypted communication]] channels) between users as well as the use of a [[virtual private network]] (VPN) per VPC user, securing, by means of authentication and encryption, the remote access of the organization to its VPC resources.<ref>{{Cite web \|title=What is Amazon VPC? - Amazon Virtual Private Cloud \|url=https://docs.aws.amazon.com/vpc/latest/userguide/what-is-amazon-vpc.html \|access-date=2026-06-19 \|website=docs.aws.amazon.com}}</ref>

	=== Types ===		=== Types ===