Computer data storage

2813:– A common solution to the problem is constantly maintaining an identical copy of device content on another device (typically of the same type). The downside is that this doubles the storage, and both devices (copies) need to be updated simultaneously with some overhead and possibly some delays. The upside is the possible concurrent reading of the same data group by two independent processes, which increases performance. When one of the replicated devices is detected to be defective, the other copy is still operational and is being utilized to generate a new copy on another device (usually available operational in a pool of stand-by devices for this purpose). 110: 873: 1667: 998: 64: 351: 1636: 2850:

the probability of two failures in the same RAID group in time proximity is much smaller (approximately the probability squared, i.e., multiplied by itself). If a database cannot tolerate even such a smaller probability of data loss, then the RAID group itself is replicated (mirrored). In many cases such mirroring is done geographically remotely, in a different storage array, to handle recovery from disasters (see disaster recovery above).

738:) differs from primary storage in that it is not directly accessible by the CPU. The computer usually uses its input/output channels to access secondary storage and transfer the desired data to primary storage. Secondary storage is non-volatile (retaining data when its power is shut off). Modern computer systems typically have two orders of magnitude more secondary storage than primary storage because secondary storage is less expensive. 40: 83: 306:) is typically corrected upon detection. A bit or a group of malfunctioning physical bits (the specific defective bit is not always known; group definition depends on the specific storage device) is typically automatically fenced out, taken out of use by the device, and replaced with another functioning equivalent group in the device, where the corrected bit values are restored (if possible). The 3213: 2909:(SAN) is a specialized network, that provides other computers with storage capacity. The crucial difference between NAS and SAN, is that NAS presents and manages file systems to client computers, while SAN provides access at block-addressing (raw) level, leaving it to attaching systems to manage data or file systems within the provided capacity. SAN is commonly associated with 2625:, has long been used to store information for automatic processing, particularly before general-purpose computers existed. Information was recorded by punching holes into the paper or cardboard medium and was read mechanically (or later optically) to determine whether a particular location on the medium was solid or contained a hole. 1964:. 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: 2731:. Holographic storage can utilize the whole volume of the storage medium, unlike optical disc storage, which is limited to a small number of surface layers. Holographic storage would be non-volatile, sequential-access, and either write-once or read/write storage. It might be used for secondary and off-line storage. See 1014:

Storage technologies at all levels of the storage hierarchy can be differentiated by evaluating certain core characteristics as well as measuring characteristics specific to a particular implementation. These core characteristics are volatility, mutability, accessibility, and addressability. For any

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Robotic-access storage devices may have a number of slots, each holding individual media, and usually one or more picking robots that traverse the slots and load media to built-in drives. The arrangement of the slots and picking devices affects performance. Important characteristics of such storage

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Device mirroring and typical RAID are designed to handle a single device failure in the RAID group of devices. However, if a second failure occurs before the RAID group is completely repaired from the first failure, then data can be lost. The probability of a single failure is typically small. Thus

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removable mass storage media into a storage device according to the system's demands; such data are often copied to secondary storage before use. It is primarily used for archiving rarely accessed information since it is much slower than secondary storage (e.g. 5–60 seconds vs. 1–10 milliseconds).

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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. It shares some technologies with cinema film stock and optical discs, but is compatible with neither. The motivation behind

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on HDDs reaches the proper placement and the data, subsequent data on the track are very fast to access. To reduce the seek time and rotational latency, data are transferred to and from disks in large contiguous blocks. Sequential or block access on disks is orders of magnitude faster than random

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is an intermediate stage between ultra-fast registers and much slower main memory. It was introduced solely to improve the performance of computers. Most actively used information in the main memory is just duplicated in the cache memory, which is faster, but of much lesser capacity. On the other

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In modern personal computers, most secondary and tertiary storage media are also used for off-line storage. Optical discs and flash memory devices are the most popular, and to a much lesser extent removable hard disk drives; older examples include floppy disks and Zip disks. In enterprise uses,

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methods allow in many cases (such as a database) to represent a string of bits by a shorter bit string ("compress") and reconstruct the original string ("decompress") when needed. This utilizes substantially less storage (tens of percent) for many types of data at the cost of more computation

965:. The medium is recorded, usually in a secondary or tertiary storage device, and then physically removed or disconnected. It must be inserted or connected by a human operator before a computer can access it again. Unlike tertiary storage, it cannot be accessed without human interaction. 984:

since it is physically inaccessible from a computer, and data confidentiality or integrity cannot be affected by computer-based attack techniques. Also, if the information stored for archival purposes is rarely accessed, off-line storage is less expensive than tertiary storage.

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access, and many sophisticated paradigms have been developed to design efficient algorithms based on sequential and block access. Another way to reduce the I/O bottleneck is to use multiple disks in parallel to increase the bandwidth between primary and secondary memory.

147:, which puts fast but expensive and small storage options close to the CPU and slower but less expensive and larger options further away. Generally, the fast technologies are referred to as "memory", while slower persistent technologies are referred to as "storage". 2771:. It was first done in 2012, when researchers achieved a ratio of 1.28 petabytes per gram of DNA. In March 2017 scientists reported that a new algorithm called a DNA fountain achieved 85% of the theoretical limit, at 215 petabytes per gram of DNA. 676:

run programs directly from ROM (or similar), because such programs are rarely changed. Standard computers do not store non-rudimentary programs in ROM, and rather, use large capacities of secondary storage, which is non-volatile as well, and not as costly.

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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. Such characteristic is typical of off-line

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of the material. Phase-change memory would be non-volatile, random-access read/write storage, and might be used for primary, secondary and off-line storage. Most rewritable and many write-once optical disks already use phase-change material to store

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As of 2011, the most commonly used data storage media are semiconductor, magnetic, and optical, while paper still sees some limited usage. Some other fundamental storage technologies, such as all-flash arrays (AFAs) are proposed for development.

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requires constant power to maintain the stored information. The fastest memory technologies are volatile ones, although that is not a universal rule. Since the primary storage is required to be very fast, it predominantly uses volatile memory.

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While a group of bits malfunction may be resolved by error detection and correction mechanisms (see above), storage device malfunction requires different solutions. The following solutions are commonly used and valid for most storage devices:

321:(compress and decompress when needed). Analysis of the trade-off between storage cost saving and costs of related computations and possible delays in data availability is done before deciding whether to keep certain data compressed or not. 186:

Without a significant amount of memory, a computer would merely be able to perform fixed operations and immediately output the result. It would have to be reconfigured to change its behavior. This is acceptable for devices such as desk

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Allows information to be overwritten at any time. A computer without some amount of read/write storage for primary storage purposes would be useless for many tasks. Modern computers typically use read/write storage also for secondary

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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.

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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.

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since the detached medium can easily be physically transported. Additionally, it is useful for cases of disaster, where, for example, a fire destroys the original data, a medium in a remote location will be unaffected, enabling

162:'s Analytical Machine, clearly distinguished between processing and memory (Babbage stored numbers as rotations of gears, while Ludgate stored numbers as displacements of rods in shuttles). This distinction was extended in the 297:

bit value flipping, or "physical bit fatigue", loss of the physical bit in the storage of its ability to maintain a distinguishable value (0 or 1), or due to errors in inter or intra-computer communication. A random

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As the RAM types used for primary storage are volatile (uninitialized at start up), a computer containing only such storage would not have a source to read instructions from, in order to start the computer. Hence,

4171: 512:, is the only one 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. 2749:

that can store electric charge. Molecular memory might be especially suited for primary storage. The theoretical storage capacity of molecular memory is 10 terabits per square inch (16 Gbit/mm).

1430:. In modern computers, location-addressable storage usually limits to primary storage, accessed internally by computer programs, since location-addressability is very efficient, but burdensome for humans. 293:

By adding bits to each encoded unit, redundancy allows the computer to detect errors in coded data and correct them based on mathematical algorithms. Errors generally occur in low probabilities due to

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for tertiary storage. It may make sense to separate read latency and write latency (especially for non-volatile memory) and in case of sequential access storage, minimum, maximum and average latency.

1311:(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 3217: 3976: 1556:

may also be used. As with latency, read rate and write rate may need to be differentiated. Also accessing media sequentially, as opposed to randomly, typically yields maximum throughput.

2394:. The deformities may be permanent (read only media), formed once (write once media) or reversible (recordable or read/write media). The following forms are in common use as of 2009: 2825:) – This method generalizes the device mirroring above by allowing one device in a group of devices to fail and be replaced with the content restored (Device mirroring is RAID with 1304:

is a form of volatile memory similar to DRAM with the exception that it never needs to be refreshed as long as power is applied; it loses its content when the power supply is lost.

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The rate at which information can be read from or written to the storage. In computer data storage, throughput is usually expressed in terms of megabytes per second (MB/s), though

839:) to a swap file or page file on secondary storage, retrieving them later when needed. If a lot of pages are moved to slower secondary storage, the system performance is degraded. 562:

to improve both reading and writing performance. Operating systems borrow RAM capacity for caching so long as it's not needed by running software. Spare memory can be utilized as

835:, allowing the utilization of more primary storage capacity than is physically available in the system. As the primary memory fills up, the system moves the least-used chunks ( 2922:

Large quantities of individual magnetic tapes, and optical or magneto-optical discs may be stored in robotic tertiary storage devices. In tape storage field they are known as

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Hardware memory encryption is available in Intel Architecture, supporting Total Memory Encryption (TME) and page granular memory encryption with multiple keys (MKTME). and in

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Any location in storage can be accessed at any moment in approximately the same amount of time. Such characteristic is well suited for primary and secondary storage. Most

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to fetch the medium and place it in a drive. When the computer has finished reading the information, the robotic arm will return the medium to its place in the library.

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Read/write storage which allows information to be overwritten multiple times, but with the write operation being much slower than the read operation. Examples include

1707:, of which high counts signify deteriorating and/or low-quality media. Too many consecutive minor errors can lead to data corruption. Not all vendors and models of 3939: 942:

For example, always-on spinning hard disk drives are online storage, while spinning drives that spin down automatically, such as in massive arrays of idle disks (

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to store information. These primary storage devices were short-lived in the market, since the Williams tube was unreliable, and the Selectron tube was expensive.

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The compactness of stored information. It is the storage capacity of a medium divided with a unit of length, area or volume (e.g. 1.2 megabytes per square inch).

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have no moving parts and consume less power than hard disks. Also, memory may use more power than hard disks. Large caches, which are used to avoid hitting the

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to perform various calculations or other operations on this data (or with the help of it). Registers are the fastest of all forms of computer data storage.

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Most contemporary computers use volatile technologies (which lose data when power is off); early computers used both volatile and persistent technologies.

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Storage devices that reduce fan usage automatically shut-down during inactivity, and low power hard drives can reduce energy consumption by 90 percent.

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Light induced magnetization melting in magnetic photoconductors has also been proposed for high-speed low-energy consumption magneto-optical storage.

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surface stores information. The information is read optically and written by combining magnetic and optical methods. Magneto-optical disc storage is

880:, with tape cartridges placed on shelves in the front, and a robotic arm moving in the back. The visible height of the library is about 180 cm. 1837: 2069: 203:

and data. Such computers are more versatile in that they do not need to have their hardware reconfigured for each new program, but can simply be

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are possible expansion options: adding slots, modules, drives, robots. Tape libraries may have from 10 to more than 100,000 slots, and provide

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is from the CPU. This traditional division of storage to primary, secondary, tertiary, and off-line storage is also guided by cost per bit.

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1476:(computer device), with hardware being faster but more expensive option. Hardware content addressable memory is often used in a computer's 3711: 1285:

retains the stored information even if not constantly supplied with electric power. It is suitable for long-term storage of information.

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The size of the largest "chunk" of data that can be efficiently accessed as a single unit, e.g. without introducing additional latency.

4099: 239:, equal to 8 bits. A piece of information can be handled by any computer or device whose storage space is large enough to accommodate 2930:, or optical disk libraries per analogy. The smallest forms of either technology containing just one drive device are referred to as 3539: 2683:

to store information. Delay-line memory was dynamic volatile, cycle sequential read/write storage, and was used for primary storage.

2386:, stores information in deformities on the surface of a circular disc and reads this information by illuminating the surface with a 672:, as updates to them are possible; however it is slow and memory must be erased in large portions before it can be re-written. Some 4371: 3566: 2845:, at the cost of more processing during both regular operation (with often reduced performance) and defective device replacement. 4201: 3765: 3593: 3404: 1808:(SSDs) as default configuration options for the secondary storage either in addition to or instead of the more traditional HDD. 550:(RAM). It is small-sized, light, but quite expensive at the same time. The particular types of RAM used for primary storage are 3887: 2513: 3355: 3222: 631:(MMU) is a small device between CPU and RAM recalculating the actual memory address, for example to provide an abstraction of 569:

As shown in the diagram, traditionally there are two more sub-layers of the primary storage, besides main large-capacity RAM:

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developing this technology was the possibility of far greater storage capacities than either magnetic tape or optical discs.

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This is primarily useful for extraordinarily large data stores, accessed without human operators. Typical examples include

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to make the operation more understandable. In modern computers, secondary, tertiary and off-line storage use file systems.

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between successive computations to build up complex procedural results. Most modern computers are von Neumann machines.

2862:. This concept does not pertain to the primary storage, which is shared between multiple processors to a lesser degree. 2629:

make it possible for objects that are sold or transported to have some computer-readable information securely attached.

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Each individually accessible unit of information is selected based on the basis of (part of) the contents stored there.

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with new in-memory instructions; they also tend to be simpler to design, in that a relatively simple processor may keep

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particular implementation of any storage technology, the characteristics worth measuring are capacity and performance.

2134: 1351:(WORM) allows the information to be written only once at some point after manufacture. Examples include semiconductor 3646:"Power consumption – Tom's hardware : Conventional hard drive obsoletism? Samsung's 32 GB flash drive previewed" 3645: 3275: 2506: 1746: 17: 4223: 1655: 1296:

is a form of volatile memory that also requires the stored information to be periodically reread and rewritten, or

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in storage to prevent the possibility of unauthorized information reconstruction from chunks of storage snapshots.

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The total amount of stored information that a storage device or medium can hold. It is expressed as a quantity of

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Relatively small amounts of digital data (compared to other digital data storage) may be backed up on paper as a

1823: 174:(ALU). The former controls the flow of data between the CPU and memory, while the latter performs arithmetic and 143:(CPU) of a computer is what manipulates data by performing computations. In practice, almost all computers use a 3791: 2869:(DAS) is a traditional mass storage, that does not use any network. This is still a most popular approach. This 943: 591:

hand, main memory is much slower, but has a much greater storage capacity than processor registers. Multi-level

5191: 5186: 5059: 3484: 2055: 1453: 5089: 4899: 3333: 1352: 516: 248: 231:. Text, numbers, pictures, audio, and nearly any other form of information can be converted into a string of 989:

magnetic tape cartridges are predominant; older examples include open-reel magnetic tape and punched cards.

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long-unused files from fast hard disk storage to libraries or jukeboxes. If the files are needed, they are

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storage to RAM and start to execute it. A non-volatile technology used for this purpose is called ROM, for

577: 235:, or binary digits, each of which has a value of 0 or 1. The most common unit of storage is the 4988: 4564: 4506: 3326:"Primary storage or storage hardware (shows usage of term "primary storage" meaning "hard disk storage")" 3041: 2413:: Read only storage, used for mass distribution of digital information (music, video, computer programs); 1644: 1465: 1301: 946:), are nearline storage. Removable media such as tape cartridges that can be automatically loaded, as in 935:

Nearline storage is not immediately available, but can be made online quickly without human intervention.

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because it is "near to online". The formal distinction between online, nearline, and offline storage is:

761:(billionths of a second). Thus, secondary storage is significantly slower than primary storage. Rotating 554:, meaning that they lose the information when not powered. Besides storing opened programs, it serves as 3525: 824:

describing the owner of a certain file, the access time, the access permissions, and other information.

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Flash storage may experience downspiking transfer rates as a result of accumulating errors, which the

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to store information in an X–Y addressable matrix and reads the information by observing the varying

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When a computer needs to read information from the tertiary storage, it will first consult a catalog

359: 192: 3311: 2879:(NAS) is mass storage attached to a computer which another computer can access at file level over a 2636:

for very long-term storage, as the longevity of paper typically exceeds even magnetic data storage.

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Offline storage is not immediately available, and requires some human intervention to become online.

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In modern computers, primary storage almost exclusively consists of dynamic volatile semiconductor

1617: 208: 196: 163: 1704: 1670: 1196: 4817: 4812: 4700: 4673: 4328: 4140: 3865: 3679: 3421: 3393:. Series on foundations and trends in theoretical computer science. Hanover, MA: now Publishers. 2866: 2485: 2460: 2114: 2108: 2102: 2096: 1750: 1693: 1149: 962: 624: 355: 307: 140: 950:, are nearline storage, while tape cartridges that must be manually loaded are offline storage. 773:

drives, have even longer access times. Other examples of secondary storage technologies include

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of near-line information. Optical jukeboxes are somewhat smaller solutions, up to 1,000 slots.

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to determine which tape or disc contains the information. Next, the computer will instruct a

817: 757:(thousandths of a second), while the access time per byte for primary storage is measured in 581: 383: 379: 263: 228: 171: 3835: 1769:

forms of semiconductor memory exist, the former using standard MOSFETs and the latter using

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Each individually accessible unit of information in storage is selected with its numerical

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is a level below secondary storage. Typically, it involves a robotic mechanism which will

8: 5125: 5044: 4569: 3547: 3137: 2896: 2888: 2699: 2366: 1529: 1282: 640: 90: 4266: 4133:"New method of self-assembling nanoscale elements could transform data storage industry" 4114: 4059: 4286: 4076: 4045: 4033: 3069: 3064: 2931: 2880: 2614: 2529: 1753:. A semiconductor memory chip may contain millions of memory cells, consisting of tiny 1742: 1708: 1643:

Distinct types of data storage have different points of failure and various methods of

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directory and file names. The underlying device is still location-addressable, but the

972: 847: 762: 648: 623:, that indicates the desired location of data. Then it reads or writes the data in the 573: 536: 275: 3562: 5110: 5020: 4717: 4581: 4479: 4391: 4278: 4193: 4081: 3891: 3769: 3589: 3394: 3385: 3361: 3281: 3271: 3132: 3095: 3026: 3009: 2884: 2680: 2676: 2672: 2589: 2287: 2125: 1805: 1597: 1568:

The probability of spontaneous bit value change under various conditions, or overall

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Main memory is directly or indirectly connected to the central processing unit via a

520: 413: 175: 155: 144: 4290: 3940:"MacBook Air replaces the standard notebook hard disk for solid state flash storage" 961:

is computer data storage on a medium or a device that is not under the control of a

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2.5-inch hard disk drives often consume less power than larger ones. Low capacity

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provide random access, though both semiconductor and flash memories have minimal

1397: 1286: 1027: 905: 843: 774: 742: 673: 659:(the terminology may be somewhat confusing as most ROM types are also capable of 587: 551: 488: 421: 311: 267: 151: 3490:

Federal Standard 1037C – Telecommunications: Glossary of Telecommunication Terms

1315:, have integrated batteries that maintain volatile storage for several minutes. 5161: 5025: 4777: 4678: 4448: 4431: 4342: 4323: 4164:"This speck of DNA contains a movie, a computer virus, and an Amazon gift card" 3917: 3122: 3036: 3019: 2935: 2923: 2808: 2786: 2657: 2633: 2154: 2022: 1912: 1858: 1686: 1666: 1445: 1427: 1297: 947: 901: 832: 632: 620: 997: 531:

as primary storage. By 1954, those unreliable methods were mostly replaced by

63: 5180: 5146: 5030: 4879: 4869: 4849: 4665: 4591: 4544: 4489: 4484: 4436: 3493:(Technical report). General Services Administration. FS-1037C. Archived from 3054: 2910: 2649: 2471: 1953: 1924: 1864: 1785: 1758: 1738: 1700: 1440: 1383: 1312: 867: 813: 661: 524: 371: 325: 159: 4356: 4274: 4015: 3623: 3285: 2957:, and for high-capacity archives in imaging, medical, and video industries. 2757:

store magnetic information, which can be modified by low-light illumination.

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and is slow write, fast read storage used for tertiary and off-line storage.

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Retains the information stored at the time of manufacture. Examples include

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The time it takes to access a particular location in storage. The relevant

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when compared to hard disk drives, as no mechanical parts need to be moved.

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consists of storage devices and their media not directly accessible by the

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hard disk drive (HDD) from 1999. When connected to a computer it serves as

71: 33: 3994:"Comparing SSD and HDD - A comprehensive comparison of the storage drives" 3809: 3692: 1255:

Mid-term archival, routine backups, server, workstation storage expansion

5151: 4854: 4822: 4725: 4685: 4648: 4616: 4458: 4034:"Optically switched magnetism in photovoltaic perovskite CH3NH3(Mn:Pb)I3" 3085: 3014: 2994: 2661: 2387: 2010: 2006: 1974: 1918: 1870: 1815: 1601: 1537: 1433: 809: 778: 754: 750: 619:. The CPU firstly sends a number through an address bus, a number called 612: 528: 350: 329: 4067: 2482:, slow write, fast read storage used for tertiary and off-line storage. 2453:: Slow write, fast read storage, used for tertiary and off-line storage; 2047: 467:. Meanwhile, slower persistent storage devices have been referred to as 4586: 4516: 4511: 4501: 3147: 3107: 2768: 2618: 2571: 1651: 1581: 1533: 1168: 1005: 812:

format, which provides the abstraction necessary to organize data into

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Various forms of storage, divided according to their distance from the

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machines differ in having a memory in which they store their operating

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A secondary or tertiary storage may connect to a computer utilizing

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Generally, the lower a storage is in the hierarchy, the lesser its

252: 220: 125: 87: 68: 52: 44: 39: 4251:"DNA Fountain enables a robust and efficient storage architecture" 3312:"Documentation for /proc/sys/vm/ — The Linux Kernel documentation" 3048: 1639:

S.M.A.R.T. software warning suggests impending hard drive failure.

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in some uses refer to what was historically called, respectively,

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the computer, that is, to read a larger program from non-volatile

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of data (often 32 or 64 bits). CPU instructions instruct the

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are located inside the processor. Each register typically holds a

535:. Core memory remained dominant until the 1970s, when advances in 82: 4636: 4574: 4528: 3258:

Computer organization and design: The hardware/software interface

2746: 2724: 2626: 2601: 2548: 2544: 2446: 2442: 2331: 2166: 2087: 1002: 310:(CRC) method is typically used in communications and storage for 259: 3693:

Karen Scarfone; Murugiah Souppaya; Matt Sexton (November 2007).

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is estimable using S.M.A.R.T. diagnostic data that includes the

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volume and virtual disk encryption, andor file/folder encryption

136:. It is a core function and fundamental component of computers. 5074: 5069: 4750: 4523: 3695:"Guide to storage encryption technologies for end user devices" 2954: 2438: 2424: 2410: 2402: 2299: 2269: 2263: 2172: 2160: 1797: 1754: 1689:

and the count of spin-ups, though its reliability is disputed.

1674: 1577: 1541: 1370: 704: 358:. The fundamental components of a general-purpose computer are 294: 287: 4950: 3483: 1784:(DRAM). Since the turn of the century, a type of non-volatile 1745:(IC) chips to store information. Data are typically stored in 1677:. The minor errors are correctable and within a healthy range. 251:, about 1250 pages in print, can be stored in about five 5130: 5079: 5004: 4012:"The DVD FAQ - A comprehensive reference of DVD technologies" 3540:"How much of the [re]drive is actually eco-friendly?" 2554: 2450: 2434: 2431:: Write once storage, used for tertiary and off-line storage; 2420: 2337: 2216: 1624: 1335: 1060: 279: 48: 4100:"A paper-based backup solution (not as stupid as it sounds)" 4827: 4721: 3766:"Introduction to SPARC M7 and silicon secured memory (SSM)" 2821: 2790: 2428: 2416: 2210: 2204: 1498: 1444:

of variable length, and a particular file is selected with

1356: 644: 401: 283: 236: 224: 1650:

Vulnerabilities that can instantly lead to total loss are

599:

being smallest, fastest and located inside the processor;

4807: 4631: 2406: 2145: 1960:

coated surface to store information. Magnetic storage is

1494: 1339: 1008: 770: 409: 232: 3970:"Comparing SSD and HDD endurance in the age of QLC SSDs" 3357:

The Essentials of Computer Organization and Architecture

2035:

Magnetic tape was then often used for secondary storage.

4321: 2398: 2001:

In early computers, magnetic storage was also used as:

766: 214: 3914:"MacBook Air – The best of iPad meets the best of Mac" 2470:

is optical disc storage where the magnetic state on a

2390:

and observing the reflection. Optical disc storage is

4224:"DNA could store all of the world's data in one room" 3888:"Mac Pro – Storage and RAID options for your Mac Pro" 3858:"Toshiba tosses hat into notebook flash storage ring" 3828:"New Samsung notebook replaces hard drive with flash" 241:

the binary representation of the piece of information

2961:

is a most known archiving strategy of automatically

2639: 2032:) or off line storage in the form of magnetic cards; 808:

Secondary storage is often formatted according to a

611:. It is actually two buses (not on the diagram): an 255:(40 million bits) with one byte per character. 3792:"What S.M.A.R.T. hard disk errors actually tell us" 753:per byte for HDDs or SSDs is typically measured in 113:

Read/Write DVD drive with cradle for media extended

3387:Algorithms and data structures for external memory 3255: 749:(SSDs) are usually used as secondary storage. The 3700:. National Institute of Standards and Technology. 3253: 5178: 1630: 1584:can be used to measure IO performance in Linux. 932:Online storage is immediately available for I/O. 274:object. Many standards exist for encoding (e.g. 166:, where the CPU consists of two main parts: The 4249:Erlich, Yaniv; Zielinski, Dina (2 March 2017). 4248: 4027: 4025: 3254:Patterson, David A.; Hennessy, John L. (2005). 3049:Secondary, tertiary and off-line storage topics 2873:was coined recently, together with NAS and SAN. 1620:is readily available for most storage devices. 1201:Indicated by downward spikes in transfer rates 3669: 3667: 428:drives, and other devices slower than RAM but 370:devices. Technology and capacity as in common 4936: 4905:History of computing hardware (1960s–present) 4386: 4372: 3676:"SSD, i-RAM and traditional hard disk drives" 3673: 3118:Noise-predictive maximum-likelihood detection 2514: 2063: 1831: 992: 27:Storage of digital data readable by computers 4022: 3380: 2528: 3744:"A proposed API for full-memory encryption" 3664: 3249: 3247: 3245: 3168: 1604:, may also consume a large amount of power. 4943: 4929: 4379: 4365: 3622:. 12 July 2006. p. 13. Archived from 3616:"Super Talent's 2.5" IDE flash hard drive" 3563:"IS the Silent PC Future 2.5-inches wide?" 3459:IBM developer-works, inside system storage 3446: 2521: 2507: 2070: 2056: 1845: 1838: 1824: 439:has, depending on technology, been called 4341: 4075: 4049: 3587: 3560: 2977: 2077: 1991:, used for tertiary and off-line storage; 4112: 3242: 1804:manufacturers started using flash-based 1665: 1634: 996: 871: 432:(retaining contents when powered down). 349: 108: 81: 62: 38: 32:For broader coverage of this topic, see 4031: 3452: 3360:. Jones & Bartlett Learning. 2006. 2853: 2775: 1452:of a computer provides the file system 1265:Portable electronics; operating system 566:for temporary high-speed data storage. 339: 14: 5179: 3434:from the original on 27 September 2007 2895:. NAS is commonly associated with the 668:Many types of "ROM" are not literally 4924: 4360: 3890:. Apple. 27 July 2006. Archived from 3596:from the original on 5 September 2008 2502: 2051: 1819: 1324:Read/write storage or mutable storage 980:. Off-line storage increases general 404:(dynamic RAM) or other such devices. 4951: 4910:List of pioneers in computer science 4032:Náfrádi, Bálint (24 November 2016). 3982:from the original on 9 October 2022. 3768:. swisdev.oracle.com. Archived from 3410:from the original on 4 January 2011. 2817:Redundant array of independent disks 2723:stores information optically inside 2704:uses different mechanical phases of 722: 643:containing a small startup program ( 627:using the data bus. Additionally, a 543:to become economically competitive. 314:. A detected error is then retried. 215:Data organization and representation 97:storage. When used within a robotic 3724:from the original on 9 October 2022 953: 857: 262:by assigning a bit pattern to each 24: 4322:Goda, K.; Kitsuregawa, M. (2012). 4315: 4226:. Science Magazine. 2 March 2017. 4113:Sterling, Bruce (16 August 2012). 3946:. 15 November 2010. Archived from 3455:"Correct use of the term nearline" 2917: 2841:saves storage, when compared with 1705:measuring correctable minor errors 1661: 1627:M7 generation since October 2015. 1135:Lack of random access (very slow) 922:Tertiary storage is also known as 482: 25: 5203: 4230:from the original on 2 March 2017 4204:from the original on 2 March 2017 4174:from the original on 3 March 2017 3569:from the original on 20 July 2008 2640:Other storage media or substrates 2459:or UDO is similar in capacity to 1417: 854:, are usually block-addressable. 842:The secondary storage, including 603:being somewhat larger and slower. 195:, and other specialized devices. 150:Even the first computer designs, 4324:"The history of storage systems" 4305:"Disaster Recovery on AWS Cloud" 4161: 3216: This article incorporates 3211: 3077:used for capturing research data 1723: 1714: 1656:failure of electronic components 1377: 1247:Moderate (but expensive drives) 1227:Very low (but expensive drives) 181: 4297: 4242: 4216: 4186: 4155: 4125: 4106: 4092: 4004: 3986: 3962: 3932: 3906: 3880: 3850: 3820: 3802: 3784: 3758: 3736: 3704: 3686: 3674:Aleksey Meyev (23 April 2008). 3638: 3608: 3588:Mike Chin (18 September 2002). 3581: 3554: 3532: 3514: 3477: 3229:General Services Administration 2959:Hierarchical storage management 2926:, and in optical storage field 699:The primary storage, including 508:), often referred to simply as 4139:. 1 March 2009. Archived from 3485:National Communications System 3422:"A thesis on tertiary storage" 3414: 3374: 3348: 3318: 3304: 3292: 3192: 1788:semiconductor memory known as 1654:on mechanical hard drives and 1517: 393:is usually fast but temporary 328:, certain types of data (e.g. 124:is a technology consisting of 93:tape cartridge, an example of 13: 1: 4952:Primary computer data storage 4900:History of computing hardware 3834:. 23 May 2006. Archived from 3810:"QPxTool - check the quality" 3205: 2780: 2005:Primary storage in a form of 1983:, used for secondary storage. 1631:Vulnerability and reliability 1587: 1353:programmable read-only memory 1331:Slow write, fast read storage 1318: 1300:, otherwise it would vanish. 1277: 249:complete works of Shakespeare 4768:Network interface controller 3678:. X-bit labs. Archived from 3330:searchstorage.techtarget.com 3005:Memory cell (disambiguation) 2989:Dynamic random-access memory 2953:Robotic storage is used for 2468:Magneto-optical disc storage 1977:, used for off-line storage; 1782:dynamic random-access memory 1755:MOS field-effect transistors 1438:Information is divided into 1309:uninterruptible power supply 1294:Dynamic random-access memory 641:non-volatile primary storage 595:setup is also commonly used— 477:auxiliary/peripheral storage 7: 4565:Refreshable braille display 4507:Refreshable braille display 3522:"Energy savings calculator" 3042:Static random-access memory 2972: 2617:, typically in the form of 1952:uses different patterns of 1811: 1645:predictive failure analysis 1608: 1540:for secondary storage, and 1484: 1466:Content-addressable storage 1302:Static random-access memory 382:and the greater its access 286:, and video encodings like 10: 5208: 4343:10.1109/JPROC.2012.2189787 3561:Mike Chin (8 March 2004). 3268:Morgan Kaufmann Publishers 2984:Aperture (computer memory) 2794: 2784: 2767:stores information in DNA 2733:Holographic Versatile Disc 2043: 1727: 993:Characteristics of storage 861: 486: 343: 31: 5139: 5103: 5052: 5043: 5013: 4997: 4968: 4959: 4892: 4836: 4795: 4786: 4664: 4600: 4543: 4472: 4407: 4398: 4353:, Computer history museum 3590:"Recommended hard drives" 2564: 2537: 2347: 2311:Magneto-optic Kerr effect 2309: 2226: 2194: 2144: 2124: 2086: 1854: 1747:metal–oxide–semiconductor 1468:can be implemented using 1175: 1065: 360:arithmetic and logic unit 332:information) may be kept 193:digital signal processors 4115:"PaperBack paper backup" 3185: 3180:Storage World Conference 3175:Storage Networking World 3169:Data storage conferences 2877:Network-attached storage 2754:Magnetic photoconductors 2719:Holographic data storage 2596:Optical mark recognition 2494: 2488:has also been proposed. 1711:support error scanning. 164:Von Neumann architecture 132:that are used to retain 4674:Central processing unit 4329:Proceedings of the IEEE 4275:10.1126/science.aaj2038 3916:. Apple. Archived from 2867:Direct-attached storage 2679:in a substance such as 2669:Electro-acoustic memory 2486:3D optical data storage 1694:flash memory controller 1001:A 1 GiB module of 820:, while also providing 389:In contemporary usage, 356:central processing unit 308:cyclic redundancy check 282:, image encodings like 141:central processing unit 3814:qpxtool.sourceforge.io 3717:. software.intel.com. 3509:Federal standard 1037C 3453:Pearson, Tony (2010). 3224:Federal Standard 1037C 3218:public domain material 3123:Object(-based) storage 3113:Information repository 2978:Primary storage topics 2745:stores information in 1678: 1671:Error rate measurement 1640: 1509:Memory storage density 1472:(computer program) or 1390:semiconductor memories 1197:Error rate measurement 1162:Failure with imminent 1011: 881: 629:memory management unit 375: 114: 106: 101:, it is classified as 79: 60: 5192:Computer architecture 5187:Computer data storage 4038:Nature Communications 3998:www.stellarinfo.co.in 3975:. Micron technology. 3032:Page address register 2710:electrical resistance 2706:phase-change material 2457:Ultra Density Optical 1771:floating-gate MOSFETs 1703:can be determined by 1696:attempts to correct. 1681:Impending failure on 1669: 1638: 1536:for primary storage, 1204:(Short-term storage) 1000: 875: 741:In modern computers, 582:arithmetic logic unit 366:, storage space, and 353: 229:binary numeral system 172:arithmetic logic unit 118:Computer data storage 112: 85: 66: 42: 5157:Magnetic-core memory 4351:Memory & storage 3682:on 18 December 2008. 3528:on 21 December 2008. 3336:on 10 September 2008 3143:Virtual tape library 3091:List of file formats 3060:Hybrid cloud storage 2907:Storage area network 2887:, or in the case of 2854:Network connectivity 2776:Related technologies 1780:(RAM), particularly 1778:random-access memory 1735:Semiconductor memory 1730:Semiconductor memory 1614:Full disk encryption 1423:Location-addressable 1349:Write once read many 1258:Long-term archival, 1043:Random-access memory 982:information security 973:transfer information 802:disk read/write head 548:random-access memory 541:semiconductor memory 533:magnetic-core memory 340:Hierarchy of storage 302:(e.g. due to random 122:digital data storage 5045:Non-volatile memory 4267:2017Sci...355..950E 4068:10.1038/ncomms13406 4060:2016NatCo...713406N 3944:news.inventhelp.com 3838:on 30 December 2010 3652:. 20 September 2006 3465:on 24 November 2015 3235:on 22 January 2022. 2889:online file storage 2797:Storage replication 2700:Phase-change memory 1530:unit of measurement 1460:Content-addressable 1283:Non-volatile memory 1271:Long-term archival 1126:~150 ms (moderate) 1020: 971:storage is used to 831:use the concept of 574:Processor registers 546:This led to modern 539:technology allowed 276:character encodings 247:. For example, the 4018:on 22 August 2009. 3772:on 21 January 2019 3712:"Encryption specs" 3626:on 26 January 2012 3070:Data proliferation 3065:Data deduplication 2881:local area network 2829:). RAID groups of 2645:Vacuum-tube memory 2615:Paper data storage 2530:Paper data storage 1806:solid-state drives 1796:As early as 2006, 1743:integrated circuit 1687:hours of operation 1679: 1658:on flash storage. 1641: 1598:solid-state drives 1576:Utilities such as 1345:Write once storage 1018: 1012: 882: 747:solid-state drives 593:hierarchical cache 537:integrated circuit 376: 176:logical operations 115: 107: 80: 61: 5174: 5173: 5170: 5169: 5039: 5038: 5021:Delay-line memory 4918: 4917: 4888: 4887: 4818:Analog audio jack 4539: 4538: 4307:. 18 August 2023. 4261:(6328): 950–954. 4102:. 14 August 2012. 3950:on 23 August 2011 3862:technewsworld.com 3798:. 6 October 2016. 3550:on 5 August 2008. 3507:See also article 3487:(7 August 1996). 3400:978-1-60198-106-6 3367:978-0-7637-3769-6 3133:Solid-state drive 3096:Global filesystem 3027:Memory protection 3010:Memory management 2928:optical jukeboxes 2885:wide area network 2860:computer networks 2673:Delay-line memory 2611: 2610: 2590:Edge-notched card 2480:sequential access 2376: 2375: 2126:Professional Disc 1997:(magnetic rolls). 1946: 1945: 1757:(MOSFETs) and/or 1408:Sequential access 1362:Read only storage 1275: 1274: 1252:Main application 978:disaster recovery 906:optical jukeboxes 829:operating systems 765:devices, such as 736:auxiliary storage 728:Secondary storage 723:Secondary storage 690:secondary storage 686:secondary storage 469:secondary storage 398:read-write memory 364:control circuitry 156:Analytical Engine 145:storage hierarchy 18:Auxiliary storage 16:(Redirected from 5199: 5050: 5049: 4966: 4965: 4945: 4938: 4931: 4922: 4921: 4793: 4792: 4444:Optical trackpad 4409:Pointing devices 4405: 4404: 4381: 4374: 4367: 4358: 4357: 4347: 4345: 4309: 4308: 4301: 4295: 4294: 4246: 4240: 4239: 4237: 4235: 4220: 4214: 4213: 4211: 4209: 4190: 4184: 4183: 4181: 4179: 4159: 4153: 4152: 4150: 4148: 4137:sciencedaily.com 4129: 4123: 4122: 4110: 4104: 4103: 4096: 4090: 4089: 4079: 4053: 4029: 4020: 4019: 4014:. Archived from 4008: 4002: 4001: 3990: 3984: 3983: 3981: 3974: 3966: 3960: 3959: 3957: 3955: 3936: 3930: 3929: 3927: 3925: 3910: 3904: 3903: 3901: 3899: 3884: 3878: 3877: 3875: 3873: 3868:on 18 March 2012 3864:. Archived from 3854: 3848: 3847: 3845: 3843: 3824: 3818: 3817: 3806: 3800: 3799: 3788: 3782: 3781: 3779: 3777: 3762: 3756: 3755: 3753: 3751: 3740: 3734: 3733: 3731: 3729: 3723: 3716: 3708: 3702: 3701: 3699: 3690: 3684: 3683: 3671: 3662: 3661: 3659: 3657: 3650:tomshardware.com 3642: 3636: 3635: 3633: 3631: 3612: 3606: 3605: 3603: 3601: 3585: 3579: 3578: 3576: 3574: 3558: 3552: 3551: 3546:. Archived from 3536: 3530: 3529: 3524:. Archived from 3518: 3512: 3506: 3504: 3502: 3481: 3475: 3474: 3472: 3470: 3461:. Archived from 3450: 3444: 3443: 3441: 3439: 3433: 3426: 3418: 3412: 3411: 3409: 3392: 3378: 3372: 3371: 3352: 3346: 3345: 3343: 3341: 3332:. Archived from 3322: 3316: 3315: 3308: 3302: 3296: 3290: 3289: 3262:(3rd ed.). 3261: 3251: 3237: 3236: 3231:. Archived from 3215: 3214: 3199: 3196: 3158:Write protection 3075:Data storage tag 2741:Molecular memory 2654:cathode-ray tube 2523: 2516: 2509: 2500: 2499: 2072: 2065: 2058: 2049: 2048: 2019:thin-film memory 2015:core rope memory 1950:Magnetic storage 1847:Magnetic storage 1840: 1833: 1826: 1817: 1816: 1802:desktop computer 1683:hard disk drives 1450:operating system 1434:File addressable 1398:hard disk drives 1212:Price per space 1186:Error detection 1048:Linear tape-open 1021: 1017: 959:Off-line storage 954:Off-line storage 925:nearline storage 885:Tertiary storage 864:Nearline storage 858:Tertiary storage 775:USB flash drives 743:hard disk drives 717:byte-addressable 694:tertiary storage 674:embedded systems 657:read-only memory 635:or other tasks. 422:hard disk drives 418:tertiary storage 346:Memory hierarchy 326:security reasons 318:Data compression 221:digital computer 105:storage instead. 55:. An example of 21: 5207: 5206: 5202: 5201: 5200: 5198: 5197: 5196: 5177: 5176: 5175: 5166: 5135: 5099: 5035: 5009: 4993: 4961:Volatile memory 4955: 4949: 4919: 4914: 4884: 4832: 4782: 4660: 4654:USB flash drive 4603: 4596: 4535: 4468: 4422:Game controller 4417:Graphics tablet 4394: 4385: 4318: 4316:Further reading 4313: 4312: 4303: 4302: 4298: 4247: 4243: 4233: 4231: 4222: 4221: 4217: 4207: 4205: 4192: 4191: 4187: 4177: 4175: 4160: 4156: 4146: 4144: 4143:on 1 March 2009 4131: 4130: 4126: 4111: 4107: 4098: 4097: 4093: 4030: 4023: 4010: 4009: 4005: 3992: 3991: 3987: 3979: 3972: 3968: 3967: 3963: 3953: 3951: 3938: 3937: 3933: 3923: 3921: 3912: 3911: 3907: 3897: 3895: 3886: 3885: 3881: 3871: 3869: 3856: 3855: 3851: 3841: 3839: 3826: 3825: 3821: 3808: 3807: 3803: 3790: 3789: 3785: 3775: 3773: 3764: 3763: 3759: 3749: 3747: 3742: 3741: 3737: 3727: 3725: 3721: 3714: 3710: 3709: 3705: 3697: 3691: 3687: 3672: 3665: 3655: 3653: 3644: 3643: 3639: 3629: 3627: 3620:The tech report 3614: 3613: 3609: 3599: 3597: 3586: 3582: 3572: 3570: 3559: 3555: 3538: 3537: 3533: 3520: 3519: 3515: 3500: 3498: 3497:on 2 March 2009 3482: 3478: 3468: 3466: 3451: 3447: 3437: 3435: 3431: 3424: 3420: 3419: 3415: 3407: 3401: 3390: 3379: 3375: 3368: 3354: 3353: 3349: 3339: 3337: 3324: 3323: 3319: 3310: 3309: 3305: 3297: 3293: 3278: 3252: 3243: 3221: 3212: 3210: 3208: 3203: 3202: 3197: 3193: 3188: 3171: 3128:Removable media 3051: 2980: 2975: 2920: 2918:Robotic storage 2856: 2799: 2793: 2785:Main articles: 2783: 2778: 2642: 2612: 2607: 2560: 2533: 2527: 2497: 2380:Optical storage 2377: 2372: 2355:Laser turntable 2343: 2305: 2222: 2190: 2140: 2120: 2082: 2079:Optical storage 2076: 2046: 2028:Tertiary (e.g. 2007:magnetic memory 1995:Carousel memory 1981:Hard disk drive 1947: 1942: 1850: 1844: 1814: 1732: 1726: 1717: 1664: 1662:Error detection 1633: 1611: 1590: 1520: 1487: 1420: 1380: 1321: 1287:Volatile memory 1280: 1232:Price per unit 1132:None (instant) 1129:None (instant) 1028:Hard disk drive 1024:Characteristic 995: 963:processing unit 956: 889:tertiary memory 870: 860: 763:optical storage 732:external memory 730:(also known as 725: 682:primary storage 601:secondary cache 588:Processor cache 517:early computers 502:internal memory 496:(also known as 494:Primary storage 491: 489:Computer memory 485: 483:Primary storage 473:external memory 465:internal memory 348: 342: 312:error detection 217: 184: 152:Charles Babbage 130:recording media 128:components and 57:primary storage 37: 28: 23: 22: 15: 12: 11: 5: 5205: 5195: 5194: 5189: 5172: 5171: 5168: 5167: 5165: 5164: 5162:Twistor memory 5159: 5154: 5149: 5143: 5141: 5137: 5136: 5134: 5133: 5128: 5123: 5118: 5113: 5107: 5105: 5101: 5100: 5098: 5097: 5092: 5087: 5082: 5077: 5072: 5067: 5056: 5054: 5047: 5041: 5040: 5037: 5036: 5034: 5033: 5028: 5026:Selectron tube 5023: 5017: 5015: 5011: 5010: 5008: 5007: 5001: 4999: 4995: 4994: 4992: 4991: 4986: 4985: 4984: 4972: 4970: 4963: 4957: 4956: 4948: 4947: 4940: 4933: 4925: 4916: 4915: 4913: 4912: 4907: 4902: 4896: 4894: 4890: 4889: 4886: 4885: 4883: 4882: 4877: 4872: 4867: 4862: 4857: 4852: 4847: 4840: 4838: 4834: 4833: 4831: 4830: 4825: 4820: 4815: 4810: 4805: 4799: 4797: 4790: 4784: 4783: 4781: 4780: 4778:Expansion card 4775: 4770: 4765: 4764: 4763: 4758: 4748: 4747: 4746: 4736: 4735: 4734: 4729: 4715: 4705: 4704: 4703: 4698: 4688: 4683: 4682: 4681: 4679:Microprocessor 4670: 4668: 4662: 4661: 4659: 4658: 4657: 4656: 4651: 4641: 4640: 4639: 4634: 4629: 4619: 4614: 4608: 4606: 4598: 4597: 4595: 4594: 4589: 4584: 4579: 4578: 4577: 4567: 4562: 4561: 4560: 4549: 4547: 4545:Output devices 4541: 4540: 4537: 4536: 4534: 4533: 4532: 4531: 4521: 4520: 4519: 4509: 4504: 4499: 4498: 4497: 4487: 4482: 4476: 4474: 4470: 4469: 4467: 4466: 4461: 4456: 4451: 4449:Pointing stick 4446: 4441: 4440: 4439: 4429: 4424: 4419: 4413: 4411: 4402: 4396: 4395: 4384: 4383: 4376: 4369: 4361: 4355: 4354: 4348: 4317: 4314: 4311: 4310: 4296: 4241: 4215: 4185: 4154: 4124: 4105: 4091: 4021: 4003: 3985: 3961: 3931: 3920:on 27 May 2013 3905: 3894:on 6 June 2013 3879: 3849: 3819: 3801: 3783: 3757: 3735: 3703: 3685: 3663: 3637: 3607: 3580: 3553: 3531: 3513: 3476: 3445: 3413: 3399: 3373: 3366: 3347: 3317: 3303: 3291: 3276: 3240: 3239: 3207: 3204: 3201: 3200: 3190: 3189: 3187: 3184: 3183: 3182: 3177: 3170: 3167: 3166: 3165: 3160: 3155: 3150: 3145: 3140: 3135: 3130: 3125: 3120: 3115: 3110: 3105: 3100: 3099: 3098: 3093: 3083: 3078: 3072: 3067: 3062: 3057: 3050: 3047: 3046: 3045: 3039: 3037:Stable storage 3034: 3029: 3024: 3023: 3022: 3020:Virtual memory 3017: 3007: 3002: 2997: 2995:Memory latency 2992: 2986: 2979: 2976: 2974: 2971: 2969:back to disk. 2924:tape libraries 2919: 2916: 2915: 2914: 2904: 2874: 2855: 2852: 2847: 2846: 2814: 2787:Disk mirroring 2782: 2779: 2777: 2774: 2773: 2772: 2765: 2759: 2758: 2755: 2751: 2750: 2743: 2737: 2736: 2721: 2715: 2714: 2702: 2696: 2695: 2691: 2685: 2684: 2670: 2666: 2665: 2658:Selectron tube 2646: 2641: 2638: 2634:matrix barcode 2609: 2608: 2606: 2605: 2599: 2593: 2587: 2581: 2575: 2568: 2566: 2562: 2561: 2559: 2558: 2552: 2541: 2539: 2535: 2534: 2526: 2525: 2518: 2511: 2503: 2496: 2493: 2465: 2464: 2454: 2432: 2414: 2382:, the typical 2374: 2373: 2371: 2370: 2364: 2358: 2351: 2349: 2348:Optical Assist 2345: 2344: 2342: 2341: 2335: 2329: 2323: 2316: 2314: 2307: 2306: 2304: 2303: 2297: 2291: 2285: 2279: 2273: 2267: 2261: 2255: 2249: 2248:(20th century) 2243: 2242:(20th century) 2237: 2230: 2228: 2224: 2223: 2221: 2220: 2214: 2208: 2201: 2199: 2192: 2191: 2189: 2188: 2182: 2176: 2170: 2164: 2158: 2151: 2149: 2142: 2141: 2139: 2138: 2131: 2129: 2122: 2121: 2119: 2118: 2112: 2106: 2100: 2093: 2091: 2084: 2083: 2075: 2074: 2067: 2060: 2052: 2045: 2042: 2037: 2036: 2033: 2026: 2023:twistor memory 1999: 1998: 1992: 1986: 1985: 1984: 1978: 1944: 1943: 1941: 1940: 1934: 1928: 1922: 1916: 1910: 1904: 1898: 1892: 1886: 1880: 1874: 1868: 1862: 1855: 1852: 1851: 1843: 1842: 1835: 1828: 1820: 1813: 1810: 1759:MOS capacitors 1728:Main article: 1725: 1722: 1716: 1713: 1709:optical drives 1699:The health of 1663: 1660: 1632: 1629: 1610: 1607: 1606: 1605: 1594: 1589: 1586: 1574: 1573: 1566: 1563: 1560: 1557: 1550: 1545: 1526: 1519: 1516: 1515: 1514: 1511: 1506: 1491: 1486: 1483: 1482: 1481: 1462: 1457: 1446:human-readable 1436: 1431: 1428:memory address 1424: 1419: 1418:Addressability 1416: 1415: 1414: 1410: 1405: 1394:flash memories 1386: 1379: 1376: 1375: 1374: 1363: 1360: 1346: 1343: 1332: 1329: 1325: 1320: 1317: 1279: 1276: 1273: 1272: 1269: 1266: 1263: 1256: 1253: 1249: 1248: 1245: 1242: 1239: 1236: 1233: 1229: 1228: 1225: 1222: 1219: 1216: 1213: 1209: 1208: 1205: 1202: 1199: 1194: 1187: 1183: 1182: 1179: 1174: 1171: 1166: 1159: 1158: 1155: 1152: 1147: 1144: 1141: 1137: 1136: 1133: 1130: 1127: 1124: 1118: 1117:(access time) 1111: 1110: 1107: 1104: 1101: 1098: 1095: 1094:Random access 1091: 1090: 1087: 1084: 1081: 1078: 1075: 1071: 1070: 1069:Magnetic tape 1067: 1066:Semiconductor 1064: 1058: 1057:Magnetic disk 1055: 1051: 1050: 1045: 1040: 1035: 1030: 1025: 994: 991: 955: 952: 948:tape libraries 940: 939: 936: 933: 902:tape libraries 859: 856: 833:virtual memory 827:Most computer 724: 721: 715:, are usually 633:virtual memory 621:memory address 605: 604: 585: 529:magnetic drums 527:, or rotating 525:Williams tubes 515:Historically, 487:Main article: 484: 481: 441:central memory 435:Historically, 372:home computers 344:Main article: 341: 338: 216: 213: 183: 180: 26: 9: 6: 4: 3: 2: 5204: 5193: 5190: 5188: 5185: 5184: 5182: 5163: 5160: 5158: 5155: 5153: 5150: 5148: 5147:Bubble memory 5145: 5144: 5142: 5138: 5132: 5129: 5127: 5124: 5122: 5119: 5117: 5114: 5112: 5109: 5108: 5106: 5102: 5096: 5093: 5091: 5088: 5086: 5083: 5081: 5078: 5076: 5073: 5071: 5068: 5065: 5061: 5058: 5057: 5055: 5051: 5048: 5046: 5042: 5032: 5031:Williams tube 5029: 5027: 5024: 5022: 5019: 5018: 5016: 5012: 5006: 5003: 5002: 5000: 4996: 4990: 4987: 4983: 4979: 4978: 4977: 4974: 4973: 4971: 4967: 4964: 4962: 4958: 4953: 4946: 4941: 4939: 4934: 4932: 4927: 4926: 4923: 4911: 4908: 4906: 4903: 4901: 4898: 4897: 4895: 4891: 4881: 4878: 4876: 4873: 4871: 4868: 4866: 4863: 4861: 4858: 4856: 4853: 4851: 4850:Parallel port 4848: 4845: 4842: 4841: 4839: 4835: 4829: 4826: 4824: 4821: 4819: 4816: 4814: 4811: 4809: 4806: 4804: 4801: 4800: 4798: 4794: 4791: 4789: 4785: 4779: 4776: 4774: 4771: 4769: 4766: 4762: 4759: 4757: 4754: 4753: 4752: 4749: 4745: 4742: 4741: 4740: 4737: 4733: 4730: 4727: 4723: 4719: 4716: 4714: 4711: 4710: 4709: 4706: 4702: 4699: 4697: 4694: 4693: 4692: 4689: 4687: 4684: 4680: 4677: 4676: 4675: 4672: 4671: 4669: 4667: 4666:Computer case 4663: 4655: 4652: 4650: 4647: 4646: 4645: 4642: 4638: 4635: 4633: 4630: 4628: 4625: 4624: 4623: 4620: 4618: 4615: 4613: 4610: 4609: 4607: 4605: 4599: 4593: 4592:Graphics card 4590: 4588: 4585: 4583: 4580: 4576: 4573: 4572: 4571: 4568: 4566: 4563: 4559: 4556: 4555: 4554: 4551: 4550: 4548: 4546: 4542: 4530: 4527: 4526: 4525: 4522: 4518: 4515: 4514: 4513: 4510: 4508: 4505: 4503: 4500: 4496: 4493: 4492: 4491: 4490:Graphics card 4488: 4486: 4485:Image scanner 4483: 4481: 4478: 4477: 4475: 4471: 4465: 4462: 4460: 4457: 4455: 4452: 4450: 4447: 4445: 4442: 4438: 4435: 4434: 4433: 4430: 4428: 4425: 4423: 4420: 4418: 4415: 4414: 4412: 4410: 4406: 4403: 4401: 4400:Input devices 4397: 4393: 4390: 4382: 4377: 4375: 4370: 4368: 4363: 4362: 4359: 4352: 4349: 4344: 4339: 4336:: 1433–1440. 4335: 4331: 4330: 4325: 4320: 4319: 4306: 4300: 4292: 4288: 4284: 4280: 4276: 4272: 4268: 4264: 4260: 4256: 4252: 4245: 4229: 4225: 4219: 4203: 4199: 4195: 4189: 4173: 4169: 4165: 4158: 4142: 4138: 4134: 4128: 4120: 4116: 4109: 4101: 4095: 4087: 4083: 4078: 4073: 4069: 4065: 4061: 4057: 4052: 4047: 4043: 4039: 4035: 4028: 4026: 4017: 4013: 4007: 3999: 3995: 3989: 3978: 3971: 3965: 3949: 3945: 3941: 3935: 3919: 3915: 3909: 3893: 3889: 3883: 3867: 3863: 3859: 3853: 3837: 3833: 3829: 3823: 3815: 3811: 3805: 3797: 3793: 3787: 3771: 3767: 3761: 3745: 3739: 3720: 3713: 3707: 3696: 3689: 3681: 3677: 3670: 3668: 3651: 3647: 3641: 3625: 3621: 3617: 3611: 3595: 3591: 3584: 3568: 3564: 3557: 3549: 3545: 3541: 3535: 3527: 3523: 3517: 3510: 3496: 3492: 3491: 3486: 3480: 3464: 3460: 3456: 3449: 3430: 3423: 3417: 3406: 3402: 3396: 3389: 3388: 3383: 3377: 3369: 3363: 3359: 3358: 3351: 3335: 3331: 3327: 3321: 3313: 3307: 3300: 3295: 3287: 3283: 3279: 3277:1-55860-604-1 3273: 3269: 3265: 3260: 3259: 3250: 3248: 3246: 3241: 3238: 3234: 3230: 3226: 3225: 3219: 3195: 3191: 3181: 3178: 3176: 3173: 3172: 3164: 3161: 3159: 3156: 3154: 3151: 3149: 3146: 3144: 3141: 3139: 3136: 3134: 3131: 3129: 3126: 3124: 3121: 3119: 3116: 3114: 3111: 3109: 3106: 3104: 3101: 3097: 3094: 3092: 3089: 3088: 3087: 3084: 3082: 3079: 3076: 3073: 3071: 3068: 3066: 3063: 3061: 3058: 3056: 3055:Cloud storage 3053: 3052: 3043: 3040: 3038: 3035: 3033: 3030: 3028: 3025: 3021: 3018: 3016: 3013: 3012: 3011: 3008: 3006: 3003: 3001: 2998: 2996: 2993: 2990: 2987: 2985: 2982: 2981: 2970: 2968: 2964: 2960: 2956: 2951: 2949: 2945: 2939: 2937: 2933: 2929: 2925: 2912: 2911:Fibre Channel 2908: 2905: 2902: 2898: 2894: 2890: 2886: 2882: 2878: 2875: 2872: 2868: 2865: 2864: 2863: 2861: 2851: 2844: 2840: 2836: 2832: 2828: 2824: 2823: 2818: 2815: 2812: 2811:(replication) 2810: 2805: 2804: 2803: 2798: 2792: 2788: 2770: 2766: 2764: 2761: 2760: 2756: 2753: 2752: 2748: 2744: 2742: 2739: 2738: 2734: 2730: 2729:photopolymers 2726: 2722: 2720: 2717: 2716: 2711: 2707: 2703: 2701: 2698: 2697: 2692: 2690: 2687: 2686: 2682: 2678: 2674: 2671: 2668: 2667: 2663: 2660:used a large 2659: 2655: 2651: 2650:Williams tube 2647: 2644: 2643: 2637: 2635: 2630: 2628: 2624: 2623:punched cards 2620: 2616: 2603: 2600: 2597: 2594: 2591: 2588: 2585: 2582: 2579: 2576: 2573: 2570: 2569: 2567: 2563: 2556: 2553: 2551:(c. 3000 BCE) 2550: 2546: 2543: 2542: 2540: 2536: 2531: 2524: 2519: 2517: 2512: 2510: 2505: 2504: 2501: 2492: 2489: 2487: 2483: 2481: 2477: 2473: 2472:ferromagnetic 2469: 2462: 2461:BD-R or BD-RE 2458: 2455: 2452: 2448: 2444: 2440: 2436: 2433: 2430: 2426: 2422: 2418: 2415: 2412: 2408: 2404: 2400: 2397: 2396: 2395: 2393: 2389: 2385: 2381: 2368: 2365: 2362: 2359: 2356: 2353: 2352: 2350: 2346: 2339: 2336: 2333: 2330: 2327: 2324: 2321: 2318: 2317: 2315: 2312: 2308: 2301: 2298: 2295: 2292: 2289: 2286: 2283: 2280: 2277: 2274: 2271: 2268: 2265: 2262: 2259: 2256: 2253: 2250: 2247: 2244: 2241: 2238: 2235: 2232: 2231: 2229: 2225: 2218: 2215: 2212: 2209: 2206: 2203: 2202: 2200: 2197: 2193: 2186: 2183: 2180: 2177: 2174: 2171: 2168: 2165: 2162: 2159: 2156: 2153: 2152: 2150: 2147: 2143: 2136: 2133: 2132: 2130: 2127: 2123: 2116: 2113: 2110: 2107: 2104: 2101: 2098: 2095: 2094: 2092: 2089: 2085: 2080: 2073: 2068: 2066: 2061: 2059: 2054: 2053: 2050: 2041: 2034: 2031: 2027: 2024: 2020: 2016: 2012: 2008: 2004: 2003: 2002: 1996: 1993: 1990: 1989:Magnetic tape 1987: 1982: 1979: 1976: 1973: 1972: 1970: 1969:Magnetic disk 1967: 1966: 1965: 1963: 1959: 1955: 1954:magnetization 1951: 1938: 1935: 1932: 1929: 1926: 1923: 1920: 1917: 1914: 1911: 1908: 1905: 1902: 1899: 1896: 1893: 1890: 1887: 1884: 1881: 1878: 1875: 1872: 1869: 1866: 1863: 1860: 1857: 1856: 1853: 1848: 1841: 1836: 1834: 1829: 1827: 1822: 1821: 1818: 1809: 1807: 1803: 1799: 1794: 1791: 1787: 1786:floating-gate 1783: 1779: 1774: 1772: 1768: 1764: 1760: 1756: 1752: 1748: 1744: 1740: 1739:semiconductor 1736: 1731: 1724:Semiconductor 1721: 1715:Storage media 1712: 1710: 1706: 1702: 1701:optical media 1697: 1695: 1690: 1688: 1684: 1676: 1672: 1668: 1659: 1657: 1653: 1652:head crashing 1648: 1646: 1637: 1628: 1626: 1621: 1619: 1615: 1603: 1599: 1595: 1592: 1591: 1585: 1583: 1579: 1571: 1567: 1564: 1561: 1558: 1555: 1551: 1549: 1546: 1543: 1539: 1535: 1532:is typically 1531: 1527: 1525: 1522: 1521: 1512: 1510: 1507: 1504: 1500: 1496: 1492: 1489: 1488: 1479: 1475: 1471: 1467: 1463: 1461: 1458: 1455: 1451: 1447: 1443: 1442: 1437: 1435: 1432: 1429: 1425: 1422: 1421: 1411: 1409: 1406: 1403: 1399: 1395: 1391: 1387: 1385: 1384:Random access 1382: 1381: 1378:Accessibility 1372: 1368: 1364: 1361: 1358: 1354: 1350: 1347: 1344: 1341: 1337: 1333: 1330: 1326: 1323: 1322: 1316: 1314: 1313:EMC Symmetrix 1310: 1305: 1303: 1299: 1295: 1291: 1288: 1284: 1270: 1267: 1264: 1262:distribution 1261: 1257: 1254: 1251: 1250: 1246: 1243: 1240: 1237: 1234: 1231: 1230: 1226: 1223: 1220: 1217: 1214: 1211: 1210: 1206: 1203: 1200: 1198: 1195: 1192: 1188: 1185: 1184: 1180: 1178: 1172: 1170: 1167: 1165: 1161: 1160: 1156: 1153: 1151: 1148: 1145: 1142: 1139: 1138: 1134: 1131: 1128: 1125: 1122: 1119: 1116: 1113: 1112: 1108: 1105: 1102: 1099: 1096: 1093: 1092: 1088: 1085: 1082: 1079: 1076: 1073: 1072: 1068: 1062: 1059: 1056: 1053: 1052: 1049: 1046: 1044: 1041: 1039: 1036: 1034: 1031: 1029: 1026: 1023: 1022: 1016: 1010: 1007: 1004: 999: 990: 986: 983: 979: 974: 970: 966: 964: 960: 951: 949: 945: 937: 934: 931: 930: 929: 927: 926: 920: 918: 914: 909: 907: 903: 898: 895:(insert) and 894: 890: 886: 879: 874: 869: 868:Cloud storage 865: 855: 853: 849: 845: 840: 838: 834: 830: 825: 823: 819: 815: 811: 806: 803: 798: 796: 792: 791:punched cards 788: 784: 783:magnetic tape 780: 776: 772: 768: 764: 760: 756: 752: 748: 744: 739: 737: 733: 729: 720: 718: 714: 710: 706: 702: 697: 695: 691: 687: 683: 678: 675: 671: 666: 664: 663: 662:random access 658: 654: 650: 647:) is used to 646: 642: 636: 634: 630: 626: 622: 618: 614: 610: 602: 598: 597:primary cache 594: 589: 586: 583: 579: 575: 572: 571: 570: 567: 565: 561: 557: 553: 549: 544: 542: 538: 534: 530: 526: 522: 518: 513: 511: 507: 503: 499: 495: 490: 480: 478: 474: 470: 466: 462: 458: 454: 450: 446: 442: 438: 433: 431: 427: 423: 420:), typically 419: 415: 411: 407: 403: 399: 396: 395:semiconductor 392: 387: 385: 381: 373: 369: 365: 361: 357: 352: 347: 337: 335: 331: 327: 322: 319: 315: 313: 309: 305: 301: 296: 291: 289: 285: 281: 277: 273: 269: 265: 261: 256: 254: 250: 246: 242: 238: 234: 230: 226: 222: 212: 210: 206: 202: 198: 194: 190: 182:Functionality 179: 177: 173: 169: 165: 161: 160:Percy Ludgate 157: 153: 148: 146: 142: 137: 135: 131: 127: 123: 119: 111: 104: 100: 96: 92: 89: 84: 77: 73: 70: 65: 58: 54: 51:mounted in a 50: 46: 41: 35: 30: 19: 5085:Flash memory 4954:technologies 4756:Power MOSFET 4739:Power supply 4708:Data storage 4707: 4644:Flash memory 4622:Optical disc 4604:data storage 4333: 4327: 4299: 4258: 4254: 4244: 4232:. Retrieved 4218: 4206:. Retrieved 4197: 4188: 4176:. Retrieved 4168:The Atlantic 4167: 4157: 4145:. Retrieved 4141:the original 4136: 4127: 4118: 4108: 4094: 4041: 4037: 4016:the original 4006: 3997: 3988: 3964: 3952:. Retrieved 3948:the original 3943: 3934: 3922:. Retrieved 3918:the original 3908: 3896:. Retrieved 3892:the original 3882: 3870:. Retrieved 3866:the original 3861: 3852: 3840:. Retrieved 3836:the original 3832:Extreme tech 3831: 3822: 3813: 3804: 3795: 3786: 3774:. Retrieved 3770:the original 3760: 3748:. Retrieved 3738: 3726:. Retrieved 3706: 3688: 3680:the original 3654:. Retrieved 3649: 3640: 3628:. Retrieved 3624:the original 3619: 3610: 3598:. Retrieved 3583: 3571:. Retrieved 3556: 3548:the original 3543: 3534: 3526:the original 3516: 3499:. Retrieved 3495:the original 3489: 3479: 3467:. Retrieved 3463:the original 3458: 3448: 3436:. Retrieved 3416: 3386: 3382:J. S. Vitter 3376: 3356: 3350: 3338:. Retrieved 3334:the original 3329: 3320: 3306: 3298: 3294: 3257: 3233:the original 3223: 3209: 3194: 3153:Write buffer 3103:Flash memory 3081:Disk utility 3000:Mass storage 2966: 2962: 2952: 2940: 2936:autochangers 2921: 2883:, a private 2857: 2848: 2842: 2838: 2837:are common. 2834: 2830: 2826: 2820: 2816: 2806: 2800: 2713:information. 2689:Optical tape 2631: 2613: 2584:Punched card 2578:Punched tape 2490: 2484: 2479: 2476:non-volatile 2475: 2466: 2392:non-volatile 2391: 2384:optical disc 2378: 2246:Optical disc 2240:Optical tape 2227:Discontinued 2196:Compact disc 2038: 2000: 1962:non-volatile 1961: 1958:magnetically 1948: 1877:Ferrite core 1795: 1790:flash memory 1775: 1767:non-volatile 1766: 1762: 1751:memory cells 1733: 1718: 1698: 1691: 1680: 1649: 1642: 1622: 1612: 1575: 1570:failure rate 1490:Raw capacity 1439: 1367:mask ROM ICs 1306: 1292: 1281: 1189:Diagnostic ( 1038:Flash memory 1033:Optical disc 1013: 987: 967: 958: 957: 941: 923: 921: 910: 896: 892: 888: 884: 883: 878:tape library 841: 826: 807: 799: 779:floppy disks 755:milliseconds 740: 735: 731: 727: 726: 698: 693: 689: 685: 681: 679: 669: 667: 660: 652: 637: 625:memory cells 608: 606: 600: 596: 568: 560:write buffer 545: 514: 509: 506:prime memory 505: 501: 497: 493: 492: 476: 472: 468: 464: 461:real storage 460: 456: 452: 449:core storage 448: 444: 440: 436: 434: 430:non-volatile 426:optical disc 405: 400:, typically 390: 388: 377: 374:around 2005. 368:input/output 323: 316: 292: 257: 243:, or simply 240: 218: 205:reprogrammed 201:instructions 185: 168:control unit 149: 138: 134:digital data 121: 117: 116: 102: 99:tape library 94: 75: 56: 34:Data storage 29: 5152:Drum memory 4855:Serial port 4846:(IEEE 1394) 4823:DisplayPort 4813:Thunderbolt 4686:Motherboard 4649:Memory card 4617:Floppy disk 4459:Touchscreen 3776:28 December 3750:28 December 3728:28 December 3544:Simple tech 3086:File system 3015:Memory leak 2932:autoloaders 2891:, over the 2769:nucleotides 2677:sound waves 2662:vacuum tube 2580:(mid-1800s) 2388:laser diode 2011:core memory 1975:Floppy disk 1919:Floppy disk 1889:Stripe card 1602:memory wall 1565:Reliability 1559:Granularity 1538:millisecond 1518:Performance 1501:(e.g. 10.4 1454:abstraction 1140:Controller 1074:Volatility 1054:Technology 917:robotic arm 818:directories 810:file system 759:nanoseconds 751:access time 613:address bus 521:delay lines 498:main memory 457:main memory 445:core memory 330:credit card 223:represents 197:Von Neumann 189:calculators 5181:Categories 5140:Historical 5014:Historical 4602:Removable 4587:Sound card 4517:Sound chip 4512:Sound card 4502:Microphone 4392:components 4162:Yong, Ed. 4051:1611.08205 3206:References 3148:Wait state 3108:Geoplexing 2903:protocols. 2795:See also: 2781:Redundancy 2619:paper tape 2572:Index card 1588:Energy use 1548:Throughput 1534:nanosecond 1319:Mutability 1278:Volatility 1268:Real-time 1224:Very high 1191:S.M.A.R.T. 1169:Head crash 862:See also: 787:paper tape 745:(HDDs) or 680:Recently, 609:memory bus 556:disk cache 272:multimedia 227:using the 5064:3D XPoint 4982:DDR SDRAM 4865:PS/2 port 4860:Game port 4773:Fax modem 4612:Disk pack 4464:Trackball 4427:Light pen 4044:: 13406. 3796:Backblaze 3746:. Lwn.net 3501:8 October 3469:16 August 3264:Amsterdam 3163:Cold data 2967:retrieved 2963:migrating 2948:petabytes 2944:terabytes 2913:networks. 2809:mirroring 2538:Antiquity 2367:Super DLT 2361:Floptical 2252:LaserDisc 2234:Microform 1937:Racetrack 1901:Thin film 1883:Hard disk 1503:megabytes 1478:CPU cache 1298:refreshed 1260:hard copy 1241:Moderate 1235:Moderate 1177:Circuitry 1164:data loss 1157:External 1154:Internal 1146:External 1143:Internal 1086:Volatile 1019:Overview 800:Once the 795:RAM disks 709:NOR flash 670:read only 653:secondary 649:bootstrap 564:RAM drive 414:secondary 380:bandwidth 334:encrypted 304:radiation 264:character 258:Data are 253:megabytes 219:A modern 178:on data. 86:160 76:secondary 4844:FireWire 4837:Obsolete 4803:Ethernet 4582:Speakers 4480:Keyboard 4454:Touchpad 4389:computer 4291:13470340 4283:28254941 4228:Archived 4202:Archived 4198:phys.org 4172:Archived 4086:27882917 3977:Archived 3719:Archived 3600:2 August 3594:Archived 3573:2 August 3567:Archived 3429:Archived 3405:Archived 3384:(2008). 3286:56213091 2973:See also 2901:CIFS/SMB 2893:Internet 2871:retronym 2725:crystals 2656:, and a 2627:Barcodes 2557:(105 CE) 2326:MiniDisc 2276:DataPlay 2185:DVD-R DL 2179:DVD+R DL 2115:BD-RE XL 2030:NCR CRAM 1812:Magnetic 1798:notebook 1763:volatile 1609:Security 1554:bit rate 1485:Capacity 1474:hardware 1470:software 1413:storage. 1328:storage. 1207:Unknown 1150:Internal 1123:(swift) 969:Off-line 913:database 897:dismount 876:A large 822:metadata 617:data bus 552:volatile 300:bit flip 170:and the 126:computer 103:tertiary 95:off-line 78:storage. 67:15 53:computer 5053:Current 4969:Current 4893:Related 4796:Current 4637:Blu-ray 4575:Plotter 4570:Printer 4553:Monitor 4529:Softcam 4437:Optical 4263:Bibcode 4255:Science 4234:3 March 4208:3 March 4178:3 March 4147:18 June 4077:5123013 4056:Bibcode 3954:18 June 3924:18 June 3898:18 June 3872:18 June 3842:18 June 3656:18 June 3630:18 June 3438:18 June 3340:18 June 3299:Storage 3138:Spindle 2955:backups 2807:Device 2747:polymer 2681:mercury 2652:used a 2602:Barcode 2598:(1930s) 2586:(1880s) 2574:(1640s) 2549:papyrus 2545:Writing 2447:DVD-RAM 2332:MD Data 2322:(1980s) 2320:MO disc 2288:ProData 2109:BD-R XL 2088:Blu-ray 2044:Optical 2021:and/or 1927:(~1970) 1915:(~1968) 1913:Twistor 1761:. Both 1741:-based 1524:Latency 1402:latency 1115:Latency 406:Storage 384:latency 260:encoded 43:1 5104:Future 5075:EEPROM 4998:Future 4980:e.g., 4751:MOSFET 4691:Memory 4558:Screen 4524:Webcam 4387:Basic 4289: 4281: 4084: 4074: 3397: 3364: 3284: 3274: 3044:(SRAM) 2991:(DRAM) 2839:n>2 2735:(HVD). 2604:(1948) 2592:(1904) 2565:Modern 2443:DVD+RW 2439:DVD-RW 2411:BD-ROM 2403:CD-ROM 2369:(1998) 2363:(1991) 2357:(1986) 2340:(2004) 2334:(1993) 2328:(1992) 2313:(1877) 2302:(2006) 2300:HD DVD 2296:(2004) 2290:(2003) 2284:(2003) 2278:(2002) 2272:(1999) 2270:MIL-CD 2266:(1997) 2264:GD-ROM 2260:(1979) 2254:(1978) 2236:(1870) 2219:(1997) 2213:(1991) 2207:(1988) 2198:(1982) 2187:(2005) 2181:(2004) 2175:(2002) 2169:(2001) 2167:DVD+RW 2163:(1999) 2161:DVD-RW 2157:(1997) 2148:(1995) 2137:(2004) 2128:(2003) 2117:(2010) 2111:(2010) 2105:(2006) 2099:(2006) 2090:(2006) 1939:(2008) 1933:(1995) 1925:Bubble 1921:(1969) 1909:(1962) 1903:(1962) 1897:(1956) 1891:(1956) 1885:(1956) 1879:(1949) 1873:(1932) 1867:(1928) 1861:(1898) 1749:(MOS) 1578:hdparm 1542:second 1371:CD-ROM 1121:~15 ms 1003:laptop 793:, and 711:, and 705:EEPROM 615:and a 510:memory 437:memory 391:memory 295:random 288:MPEG-4 5131:SONOS 5111:FeRAM 5080:EPROM 5070:EAROM 5005:Z-RAM 4870:eSATA 4788:Ports 4473:Other 4432:Mouse 4287:S2CID 4119:Wired 4046:arXiv 3980:(PDF) 3973:(PDF) 3722:(PDF) 3715:(PDF) 3698:(PDF) 3432:(PDF) 3425:(PDF) 3408:(PDF) 3391:(PDF) 3220:from 3186:Notes 2675:used 2555:Paper 2532:media 2495:Paper 2451:BD-RE 2435:CD-RW 2425:DVD+R 2421:DVD-R 2338:Hi-MD 2217:CD-RW 2173:DVD+R 2155:DVD-R 2103:BD-RE 2081:media 2009:, or 1956:on a 1849:media 1737:uses 1675:DVD+R 1673:on a 1625:SPARC 1499:bytes 1441:files 1336:CD-RW 1244:High 1221:High 1063:beam 1061:Laser 893:mount 837:pages 814:files 519:used 504:, or 475:, or 463:, or 280:ASCII 278:like 270:, or 268:digit 209:state 49:SDRAM 5126:PRAM 5121:NRAM 5116:MRAM 5090:PROM 5060:RRAM 4989:SRAM 4976:DRAM 4828:HDMI 4744:SMPS 4732:SSHD 4726:NVMe 4722:SATA 4701:BIOS 4279:PMID 4236:2017 4210:2017 4180:2017 4149:2011 4082:PMID 3956:2011 3926:2011 3900:2011 3874:2011 3844:2011 3778:2019 3752:2019 3730:2019 3658:2011 3632:2011 3602:2008 3575:2008 3503:2007 3471:2015 3440:2011 3395:ISBN 3362:ISBN 3342:2011 3282:OCLC 3272:ISBN 2899:and 2822:RAID 2791:RAID 2789:and 2429:BD-R 2417:CD-R 2258:WORM 2211:CD-i 2205:CD-R 2097:BD-R 1931:MRAM 1907:CRAM 1895:MICR 1871:Drum 1865:Tape 1859:Wire 1800:and 1765:and 1580:and 1495:bits 1396:and 1369:and 1357:CD-R 1355:and 1338:and 1238:Low 1218:Low 1215:Low 1106:Yes 1103:Yes 1100:Yes 1097:Yes 1006:DDR2 944:MAID 904:and 866:and 850:and 816:and 769:and 692:and 684:and 645:BIOS 578:word 558:and 453:drum 402:DRAM 324:For 284:JPEG 245:data 237:byte 233:bits 225:data 158:and 139:The 91:SDLT 72:PATA 5095:ROM 4880:VGA 4875:DVI 4808:USB 4761:VRM 4718:SSD 4713:HDD 4696:RAM 4632:DVD 4495:GPU 4338:doi 4334:100 4271:doi 4259:355 4072:PMC 4064:doi 2946:or 2934:or 2897:NFS 2843:n=2 2835:n=6 2833:or 2831:n=5 2827:n=2 2763:DNA 2727:or 2621:or 2547:on 2407:DVD 2294:UMD 2282:UDO 2146:DVD 2135:PDD 1582:sar 1497:or 1340:SSD 1307:An 1109:No 1089:No 1083:No 1080:No 1077:No 1009:RAM 887:or 852:SSD 848:ODD 844:HDD 771:DVD 734:or 713:RAM 701:ROM 665:). 416:or 410:CPU 290:). 154:'s 120:or 47:of 45:GiB 5183:: 5062:( 4724:/ 4627:CD 4332:. 4326:. 4285:. 4277:. 4269:. 4257:. 4253:. 4200:. 4196:. 4170:. 4166:. 4135:. 4117:. 4080:. 4070:. 4062:. 4054:. 4040:. 4036:. 4024:^ 3996:. 3942:. 3860:. 3830:. 3812:. 3794:. 3666:^ 3648:. 3618:. 3592:. 3565:. 3542:. 3457:. 3427:. 3403:. 3328:. 3280:. 3270:. 3266:: 3244:^ 3227:. 2938:. 2648:A 2478:, 2449:, 2445:, 2441:, 2437:, 2427:, 2423:, 2419:, 2409:, 2405:, 2401:, 2399:CD 2017:, 2013:, 1971:; 1773:. 1647:. 1616:, 1505:). 1392:, 1193:) 1181:— 1173:— 908:. 846:, 797:. 789:, 785:, 781:, 777:, 767:CD 719:. 707:, 703:, 696:. 523:, 500:, 479:. 471:, 459:, 455:, 451:, 447:, 443:, 424:, 362:, 266:, 191:, 88:GB 69:GB 5066:) 4944:e 4937:t 4930:v 4728:) 4720:( 4380:e 4373:t 4366:v 4346:. 4340:: 4293:. 4273:: 4265:: 4238:. 4212:. 4182:. 4151:. 4121:. 4088:. 4066:: 4058:: 4048:: 4042:7 4000:. 3958:. 3928:. 3902:. 3876:. 3846:. 3816:. 3780:. 3754:. 3732:. 3660:. 3634:. 3604:. 3577:. 3511:. 3505:. 3473:. 3442:. 3370:. 3344:. 3314:. 3288:. 2819:( 2522:e 2515:t 2508:v 2071:e 2064:t 2057:v 2025:; 1839:e 1832:t 1825:v 1572:. 1480:. 1373:. 1359:. 1342:. 412:( 59:. 36:. 20:)

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