Unreferenced date August 2009 Image Apertura harddisk 04.jpg thumb right 300px Harddisk with platter A harddisk platter or disk is a component of a harddisk drive it is the circular disk on which the magnetic data is stored. The rigid nature of the platters in a hard drive is what gives them their name as opposed to the flexible materials which are used to make floppy disk . Hard drives typically have several platters which are mounted on the same Harddisk drive Spindle spindle . A platter can store information on both sides, requiring two heads per platter. Description The magnetic surface ... to represent a single binary unit of information. A typical magnetic region on a harddisk platter ... of the bit given above roughly sets the scale for what constitutes a significant defect size . In the harddisk drive the Disk read and write head hard drive heads fly and move radially over the surface ... of finish are required properties of a harddisk platter. In 2005 06, a major shift in technology of harddisk drives and of magnetic disks media began. Originally, in plane magnetized materials ... of the harddisk drive such as the head and the electronic channel . DEFAULTSORT HardDisk Platter Category Harddisk drives ca Plat maquinari es Plato disco duro ko ja no Platelagerskive ... to about 100 billion bits 100 gigabit s per square inch of disk area. The material of the main magnetic medium layer is usually a cobalt based alloy. In today s hard drives each of these magnetic ... in hard drives has been in reduction of grain size . Manufacture Image Innansicht Festplatte 512 MB von Quantum.jpg thumb right 250px Inside view of a harddisk Platters are typically made using an aluminium or glass and ceramic substrate. In disk manufacturing, a thin coating is deposited on both ... on top of the sputtered structure by dipping the disk into a solvent solution, after which the disk ... size. Orienting the magnetization perpendicular to the disk surface has major implications for the disk ... more details
File Harddisk failure.jpeg thumb right 250px A head crash, one type of disk failure In computing , a harddisk failure occurs when a harddisk drive malfunctions and the stored information cannot be accessed with a properly configured computer. A disk failure may occur in the course of normal operation ... . Causes The most notorious cause of harddisk failure is a head crash , where the internal disk read and write head read and write head of the device touches a Harddisk platter platter , or a magnetic ... situations. The phenomenon of disk failure is not limited to hard drives. Other media types ... when attempting to access the drive. Signs of harddisk failure Hard drive failure can be catastrophic ... them to its own growth defect table, ref http www.pcmag.com encyclopedia term 0,2542,t harddisk defect ... a harddisk for repairs, the easiest would be to change the circuit board by using an identical hard ... then they can be transferred to another identical harddisk. However disk platter failures may require ... details. External links wikibooks Recovering data after a harddisk drive failure wikibooks Minimizing harddisk drive failure and data loss http research.google.com archive disk failures.pdf Failure Trends in a Large Disk Drive Population Google, Inc. February 2007 http datafilerecovery.net hard drive ... hard drives make http www.graffs.co.uk drive failure issues and symptoms Harddisk anatomy Logical and Physical failures References reflist DEFAULTSORT HardDisk Failure Category Harddisk drives ... recovery attempts may cause further damage if not done by a specialist with proper equipment. Hard ... risk. Another cause of failure is a faulty air filter . The air filters on today s hard drives equalize the atmospheric pressure and moisture between the hard drive enclosure and its outside environment ... a head crash if the head happens to sweep over it. After a hard drive crash, each particle from the damaged ... render a hard drive useless. A hard drive also includes controller electronics, which occasionally ... more details
main Harddisk drive In 1953 IBM recognized the immediate application for what it termed a Random Access ... the harddisk drive . ref patent US 3503060 DIRECT ACCESS MAGNETIC DISC STORAGE DEVICE March 24, 1970 ... File, ASME Award, Feb 27, 1984. ref The commercial usage of harddisk drives began in 1956 with the shipment ... required high current AC power due to the large motors required to spin the large disks. Harddisk drives .... During the mid 1990s the typical harddisk drive for a PC had a capacity of about 1 gigabyte . ref ... harddisk drives typically had a capacity of 500 to 1000 gigabyte s, while the largest capacity ... Walking Through 50 Years of HardDisk Drive History slide 6 publisher eWEEK.com url http www.eweek.com c a Data Storage Walking Through 40 Years of HardDisk Drive History 550612 accessdate 2010 .... 1980s, the PC era As the 1980s began, harddisk drives were a rare and very expensive optional feature on personal computers PCs however by the late 80s, harddisk drives were standard on all but the cheapest PC. Most harddisk drives in the early 1980s were sold to PC end users by System ... such as the Apple ProFile . The IBM PC XT in 1983 included an internal standard 10MB harddisk drive, and soon thereafter internal harddisk drives proliferated on personal computers. External hard ... microstructure for thin film disk storage media, still used today. 1991 2.5 inch 100 megabyte hard ... Response Maximum Likelihood algorithm 1992 first 1.3 inch harddisk drive HP Kittyhawk microdrive HP ... Molex power inputs Image Seagate s clean room.jpg thumb Seagate Technology Seagate harddisk drives being manufactured in a factory in Wuxi , China See also List of defunct harddisk manufacturers ... completes acquisition of samsung E2 80 99s harddisk drive business Seagate Completes Acquisition of Samsung s HardDisk Drive Business ref , Western Digital , Toshiba and HGST Hitachi HGST . Western ... failures. At some point, possibly MS DOS 3.0, soft errors were reported as diskhard errors and a subsequent ... more details
Mac specs Name HardDisk 20 Image HD20.JPG Type HardDisk Casing plastic Pantone 453 ref cite web last ... for the presence of a System file on the HardDisk, switch over to it and eject the startup disk. Unfortunately, the HD 20 could not be used as a startup disk directly without first loading the code from ... finally be used alone as a startup disk. While other hard drives were available on the market, Apple ... gives its Macintosh a harddisk work pages language publisher New York Times date 1985 10 08 url ... its April announcement. Until Apple s introduction a year later of the HardDisk 20SC , the first ... 1306 HardDisk 20 technical specifications at apple.com http docs.info.apple.com article.html?artnum 4423 Mac Systems Compatible with HardDisk 20 at apple.com http www.vintagemacworld.com hd20.html HardDisk 20 tutorial at VintageMacWorld.com http www.mac512.com macwebpages hd20.htm HardDisk ... Before System 7 Apple hardware before 1998 Category Macintosh peripherals Category Harddisk drives ... work The New York Times title Peripherals Apple Gives Its Macintosh A HardDisk first Peter H. last Lewis date 1985 10 08 accessdate 2010 05 04 ref CPU RAM OS Mac OS history 2.1 Mac OS history System Software 5 4.3 ModelNumber M0131 Price 1495 The Macintosh HardDisk 20 was the first hard drive developed by Apple Computer specifically for use with the Macintosh 512K . Introduced ... Plus in January 1986, would accommodate far faster and more efficient hard drives, rendering the HardDisk 20 virtually obsolete. ref http docs.info.apple.com article.html?artnum 8169 Macintosh 128K and 512K SCSI Hard Drives Bot generated title ref Features The HardDisk 20 or HD20 , as it was known colloquially contained a 20MB 3.5 Rodime harddisk which provided over 50 times the data storage of the stock 400K disk drive. At a time when the average file size was around 10 20K and due to the vast ..., it required an additional file in the System Folder on a special startup disk which added additional ... more details
essay like date July 2011 unreferenced date July 2011 A harddisk recorder is a type of direct to disk recording system that uses a high capacity harddisk to record digital audio or digital video . Harddisk recording systems represent an alternative to more traditional reel to reel tape or cassette ... to include harddisk recording capabilities in their high end systems. New England Digital offered the Sample to Disk digital recording option on the Synclavier , the first commercial harddisk HDD recording ... 1990s, with the steady decline of harddisk prices and the corresponding increases in capacity and portability, the cost of harddisk recording systems had dropped to the point where they became ... still in use, harddisk systems are rapidly becoming the preferred method for studio recording. On January ... Academy Awards for the development of harddisk recording technology http awardsdatabase.oscars.org ... harddisk recording system, however. Different manufacturers implement different degrees of this facility. In addition, harddisk recorders offer some disadvantages, including the limited capacity and relatively high cost of replacement drives, as well as a reduced ruggedness of harddisk recorders as compared to magnetic tape based systems. Harddisk recorders are often combined with a digital mixing ... as a harddisk recorder with appropriate software nowadays this solution is often preferred, as it provides ... constraints on any harddisk recording system are the disk size, transfer rate , and processor speed ... is becoming increasingly rare, thanks to rapid increases in harddisk capacity. Popular harddisk ... X Series Hybrid HardDisk Workstation X 48 24bit 96 kHz, 48tr Rec48tr Yamaha Corporation YAMAHA ... Related links DEFAULTSORT HardDisk Recorder Category Digital audio recording Category Television terminology it Harddisk recording ja ... . However, in 1991, Fairlight ESP Pty Ltd developed the MFX2, the first 24 track disk ... more details
Mac specs Name HardDisk 20SC Image Apple hd20sc.jpg Type HardDisk Casing plastic Pantone 453 ref cite web last Tracy first Ed title History of computer design Macintosh url http www.landsnail.com apple local design macintosh.html accessdate 2007 12 30 ref & Platinum Introduced September, 1986 Discontinued ? MSRP CPU RAM OS N A ModelNumber M2604 The Apple HardDisk 20SC not to be confused with the Apple HardDisk 20 Macintosh HardDisk 20 , the first hard drive manufactured by Apple exclusively for the original Macintosh floppy disk drive port interface was Apple s first SCSI based hard drive for the Apple II family as well as the Macintosh and other third party computers using an industry standard SCSI interface. History Released in September 1986 along with the Apple IIGS which required an optional SCSI Apple II peripheral cards interface card to use it , it debuted over 9 months after the introduction of the Macintosh Plus , the first to include Apple s SCSI interface. It was a welcome ... http docs.info.apple.com article.html?artnum 1931 Apple HardDisk 20SC Specifications Discontinued Bot generated title ref than its predecessors, the HardDisk 20 62.5 Kilobytes per second ref http docs.info.apple.com article.html?artnum 1306 HardDisk 20 Specification Discontinued ref and ProFile . ref http docs.info.apple.com article.html?artnum 1128 ProFile Hard Drive Specifications Discontinued ref Hardware The 20SC originally contained a half height 5.25 Seagate ST 225N 20MB SCSI hard drive, but was later manufactured with a full height 3.5 MiniScribe 8425SA 20MB SCSI hard drive. The latter drive was the same size as the drive inside the Macintosh HardDisk 20, but 10 to 15 MB over what ... Harddisk drives ... full height hard drive mechanism. Indeed the case design would be reused unchanged in Platinum only ... platform drive offered by Apple it was the first hard drive to use the Snow White design language ... more details
File Diagram of HardDisk Drive Manufacturer Consolidation.svg thumb 300px Diagram of consolidation It has been estimated that over 200 companies were harddisk drive manufacturers at one time or another. Besides competing on features such as harddisk HDD data density and latencies, many of those companies started to support new, smaller form factors that enabled the ever reducing physical sizes of computing devices. Most of that industry has been reduced to five strong vendors through bankruptcy and acquisition. As of 2011, these vendors are alphabetically HGST , Samsung , Seagate Technology Seagate , Toshiba , and Western Digital . The first two of these may be acquired later in 2011, which would result in only three manufacturers of hard drives. The following is a list of notable defunct HDD manufacturers Alps Electric left industry Amcodyne ref name McKendrick Ampex ref name McKendrick ... Change and Foreign Assembly in the HardDisk Drive Industry last McKendrick first David date November 1997 accessdate 2011 08 03 ref sold harddisk drive business to Seagate in 1989 Cornice ... ref name McKendrick sold harddisk drive business to Quantum Corporation Quantum in 1994 DZU ... ref name McKendrick IBM ref name McKendrick harddisk drive business acquired by Hitachi Global ... http books.google.com books?id 5XHrnDj7kG8C&pg PA23&lpg PA23&dq 22Itel 22 harddisk drive intel v onepage&q ... name McKendrick sold harddisk drive business to Maxtor in 2000 Raymond Engineering ref name McKendrick ... Defunct computer companies of the United States List of defunct harddisk manufacturers Category Harddisk drives List of defunct harddisk manufacturers Category Computing lists Defunct harddisk manufacturers Category Computer storage companies Defunct harddisk manufacturers ru ... than two years before leaving the hard drive business. Atasi Corp. bankrupt Areal Technology ref name ... Gigastorage ref name McKendrick Halo Data startup making mini disk drives for digital cameras went ... more details
Notability Products date October 2009 Refimprove date November 2009 The term disk to disk , or D2D , generally refers to disk to disk backup. With D2D, a computer harddisk is backed up to another harddisk rather than to a tape or floppy. D2D is often confused with virtual tape , but differs in that it enables multiple backup and recovery operations to simultaneously access the disk directly by using a true file system. ref citebook title Backup and recovery first W. Curtis last Preston edition 2 publisher O Reilly Media year 2006 ISBN 0596102461 pages 219 ref Typical advantages of disk to disk Higher speed and higher capacity, relative to tape or floppy, resulting in shorter backup and recovery windows. Non linear recovery of data, enabling a specific file to be restored quicker and simpler than with tape. Lower total cost of ownership due to increased automation and lower hardware costs. Citation needed date August 2008 Remote backup services Remote backup service s are closely related to D2D backup as they are most often stored remotely on disk. The only major difference is that the data tends to be held at a remote location and these services are often provided by List of backup software Managed backup providers . References refs compu storage stub Category Computer backup Category Disk cloning ... more details
Unreferenced date October 2011 Infobox short story See Wikipedia WikiProject Novels or Wikipedia WikiProject Books name The Disk title orig El Disco translator author Jorge Luis Borges country Argentina language Spanish language Spanish series genre Fantasy , short story published in The Book of Sand book The Book of Sand publisher media type Print pub date 1975 english pub date 1977 The Disk is a 1975 in literature 1975 short story written by Argentina Argentinian writer Jorge Luis Borges . It appears in the collection The Book of Sand book The Book of Sand . Synopsis The story deals with a woodcutter who lives in the midst of a deep wood in old England and who has never seen the sea. He tells the reader that at one time a man, who asks lodging from him appears at his door. The woodcutter notes that the man was elderly, as he referred to England as Saxony , which, at the time, was a sign of age. The day after the man wishes to leave, but before he does, he says that he is a King and is descended from Odin . He tells the woodcutter that he is exiled, but that he shall always be a king, because he holds the Disk of Odin, the sole thing in the world that has but one side. He opens his hand and shows the disk the woodcutter sees only an empty palm, but thereafter touches it, feeling a chill in the fingers and seeing a flash. He makes a false claim that he has a full chest of gold and wants to trade it for the disk, because he knows the man will decline. And the man does, to which the woodcutter replies that the man may go. When he turns around, the woodcutter kills the man with an axe. He then drags the body and throws it into the river. He then comes back and searches for the disk, which he never finds. See also portal Novels Bibliography of Jorge Luis Borges Jorge Luis Borges DEFAULTSORT Disk, The Category 1975 short stories Category Short stories by Jorge Luis Borges story stub es El disco ... more details
wiktionarypar hard hardness Hard or Hardness may refer to Hardness , resistance of physical materials to change under force Hard water , water with a high mineral content NP hard , a term used in Computational complexity theory Hard, Austria , a town in Austria Hard Z rich , a quarter in Z rich Hard tennis , a type of tennis court Hard music festival , concerts and live events Hard, or hard on, a slang term for an erection Hard nautical , a firm or paved beach or slope convenient for hauling vessels out of the water Hayward Area Recreation and Park District , abbreviated H.A.R.D. Music Hard band , a Hungarian hard rock supergroup Hard Brainpower album Hard Brainpower album Hard Gang of Four album Hard Gang of Four album Hard Jagged Edge album Hard Jagged Edge album Hard song Hard song , by Rihanna Disambig cs Tvrdost de Hard Begriffskl rung fr Hard it Hard nl Hard no Hardhet pt Hard ro Hard uk Hard ... more details
Infobox Album See Wikipedia WikiProject Albums Name Hard For It Type Studio Artist Cutty Ranks Cover Cutty Ranks Hard For It.jpg Released 2006 ref name vibes cite web url http www.reggae vibes.com rev sin hardfori.htm title Cutty Ranks Hard for It Review accessdate 2007 12 30 work Reggae Vibes.com ref Recorded Genre Length Label Walboomers Records ref name vibes Producer Reviews Last album This album Hard For It Next album Hard For It is an album by Cutty Ranks . The song 20 Inch was recorded in several versions, including a version with vocals by Master P . Track listing Talli Talli Remix feat. Kobra Khan What Dem Fighting For Dirty Mind Hard For It 20 Inch Mega Mix feat. Kobra Khan Head Mistress Dem A Eat Gal Strange Feeling Who Give Di Orders Wise Up Better Day Holiday Take Me Away feat. Emereld Guilty feat. A20 Turn Me On feat. Flave I Congratulate You Move To The Gal Dem 20 Inch References references http www.reggae vibes.com rev sin hardfori.htm Reggae Vibes review http www.juno.co.uk products 259011 01.htm entry at Juno.uk.co Category 2006 albums Category Cutty Ranks albums ... more details
Use British English date May 2011 Use dmy dates date May 2011 Infobox album Name It s Hard Type studio Artist The Who Cover The who its hard album.jpg Released 4 September 1982 Recorded June 1982, Turn Up Down Studio at Glyn Johns home in Surrey , England Genre Rock music Rock Length 46 29 Language English language English Label Polydor Records Polydor UK br Warner Bros. Records Warner Bros. Original ... It s Hard br 1982 Next album Endless Wire The Who album Endless Wire br 2006 Misc Singles Name It s Hard ... date 1982 Single 3 It s Hard Single 3 date 1983 Album reviews rev1 Allmusic rev1score Rating 2 5 ref ... music reviews album 3045 22014 ref noprose yes It s Hard is the tenth studio album by English ... It s Hard . Live performances Just over half of this album has been played live over the course ... performance of Athena . It s Hard was played the entire 1982 tour and regularly featured a short ... Horizon in Chicago , in place of It s Hard . This was because the song was written by Townshend ... John Entwistle 3 39 Cooks County 3 51 It s Hard 3 47 Dangerous Entwistle 3 36 Eminence Front 5 39 ... digitally remastered reissue of It s Hard added four live tracks recorded on the last show of The Who s The Who Tour 1982 1982 tour , on 17 December in Toronto . li value 13 It s Hard 4 56 Eminence Front ... Moon It s Hard Bot generated title ref align center 28 UK Singles Chart ref name chart align center ... align center 5 It s Hard Billboard Mainstream Rock ref name multiple align center 39 class wikitable ... title It s Hard artist The Who award Gold autocat yes region United States type album certification ... linernotes It sHard.htm It s Hard Liner Notes The Who Category 1982 albums Category Albums ... Records albums Category The Who albums Category Warner Bros. Records albums cs It s Hard de It s Hard es It s Hard fr It s Hard it It s Hard nl It s Hard nn It s Hard pt It s Hard ro It s Hard fi It s Hard sv It s Hard ... more details
In computing , a disk failure usually refers to the failure of a disc based storage device. These are usually either A floppy disk See buzz of death A harddisk See harddisk failure See also Fault tolerant system RAID Data redundancy Disaster recovery Data recovery Data loss Not to be confused with Spinal disc herniation Slipped disk a medical condition of a spine. disambig ... more details
shell inserted and twisted to unlock the disk platter from the drive and secure it to the top shell. The assembly would then be lifted out and the bottom cover attached. A different disk pack could then be inserted by removing the bottom and placing the disk pack with its top shell into the drive. Turning the handle would lock the disk pack in place and free the top shell for removal. The first removable disk pack was invented in 1965 by two IBM engineers, Thomas G. Leary and R. E. Pattison. Examples of a hard disks with removable disk packs are the IBM magnetic disk drives IBM 1311 IBM 1311 ... for Drum and Disk Records, U.S. Patent 3,206,214, 1965 R.E. Pattison, Portable Memory for Data Processing Machine, U.S. Patent 3,176,281, 1965 See also commonscat Removable disk packs disk cartridge , harddisk History history of harddisk DEFAULTSORT Disk Pack Category Rotating disc computer storage ...Image Nashua diskpack.jpg thumb Disk pack manufactured by Nashua, USA, without its protective cover. A 3.5 modern hard drive is shown for comparison. A Disk pack is a layered grouping of harddisk platter s circular, rigid discs coated with a magnetic data storage device data storage surface . A disk pack is the core component of a harddisk drive. In modern hard disks, the disk pack is permanently sealed inside the drive. In many early hard disks, the disk pack was a removable unit, and would be supplied with a protective canister featuring a lifting handle. The protective cover consisted of two parts, a clear plastic shell, with a handle in the center, that enclosed the top and sides of the disks and a separate bottom that completed the sealed package. To remove the disk pack, the drive would ... selects a disk pack File Fotothek df n 10 0000118.jpg Bottom cover is removed File Fotothek df n 10 0000119.jpg Disk pack is ready for insertion File IBM2314DiskDrivesAndIBM2540CardReaderPunch.jpg IBM 2314 s with removable disk packs and empty covers on top gallery References http www 03.ibm.com ... more details
Disk cache may refer to Disk buffer , the small amount of buffer memory present on a hard drive. Page cache , the cache of disk pages kept by the operating systems, stored in unused main memory. General application level cache caching of data stored on the disk. ReadyBoost , a non volatile disk cache stored on a flash memory device, in Windows Vista and Windows 7. disambig ko zh ... more details
Orphan date December 2010 Unreferenced date December 2009 Disk cartridge has several meanings related to computer storage . 1960s storage medium An early disk cartridge was a single harddisk platter encased in a protective plastic shell. When the removable cartridge was inserted into the cartridge drive peripheral device , the disk read and write head read write head s of the drive could access the magnetic data storage device data storage surface of the platter through holes in the shell. The disk cartridge was a direct evolution from the disk pack drive, or the early hard drive . As the computer storage density storage density improved, even a single platter would provide a useful amount of data storage space, with the benefit being easier to handle than a removable disk pack. An example of a cartridge drive is the IBM magnetic disk drives IBM 2310 IBM 2310 . Disk cartridges were made obsolete by floppy disk s. Expand section date June 2008 Modern storage medium Image Zip disc back.jpg thumb Zip disks are sometimes referred to as disk cartridges. Some more recent removable disk storage media are referred to as disk cartridges . This is most common with Zip drive Zip disk s. It is very rare, but not unheard of, to refer to the floppy disk 3 inch microfloppy as a disk cartridge. Protective casing Some types of optical disc s and magneto optical disc s were either permanently enclosed in a protective plastic sheath, or placed into a sheath before being inserted into the computer drive drive . This sheath was often called caddy , but sometimes also disk cartridge . See also Cartridge electronics Universal Media Disc DEFAULTSORT Disk Cartridge Category Rotating disc computer storage media ... more details
disks including both harddisk s, removable media and disk images enabling or disabling Journaling file system journaling verifying a disk s Data corruption integrity , and repairing it if the disk is damaged ... status of a harddisk. Disk Utility functions may also be accessed from the Mac OS X Command line interface command line with the code diskutil code and code hdiutil code commands. Disk Utility was updated with Mac OS X v10.3 . Prior to v10.3, the functionality of Disk Utility was spread across two applications Disk Copy and Disk Utility. Disk Copy was used for creating and mounting disk image files ... Mac OS X Category Disk partitioning software Category Harddisk software Category Data erasure ...Infobox software name Disk Utility logo Image Diskutil.png 64px screenshot Image Disk Utility screenshot.png 220px Disk Utility screenshot caption author developer Apple Inc. released latest release version ... website Disk Utility is the name of a Utility software utility created by Apple Inc. Apple for performing Disk storage disk related tasks in Mac OS X . These tasks include ref http docs.info.apple.com article.html?path DiskUtility 10.5 en duh1008.html Disk Utility 10.5 Help Testing and repairing a disk or volume ref the creation, conversion, compression and encryption of disk image s from a wide range of formats read by Disk Utility to .dmg or for CD DVD images .cdr, which is identical to the .iso ... kb HT1452 About Disk Utility s Repair Disk Permissions feature ref disk erasing, disk formatting formatting , disk partitioning partitioning ref http support.apple.com kb HT2374 Mac OS X 10.5 About resizing disk partitions ref and disk cloning cloning secure deletion of free space or disk using ... sets in Disk Utility ref , and repairing RAID sets restoring volumes from Apple Software Restore ASR images Optical disc authoring burning disk images to CD ROM CD or DVD in HFS Plus HFS format ref http support.apple.com kb HT2087 Burning a disk image file on a CD or DVD in Mac OS X ref erasing CD ... more details
Refimprove date May 2009 distinguish page cache File Fujitsu MPG3307AH ms avrs 110909.jpg thumb The disk buffer sits on the controller board of the hard drive. In computer storage , disk buffer often ambiguously Fact date September 2007 called disk cache or cache buffer Fact date September 2007 is the embedded memory in a hard drive acting as a buffer computer science buffer between the rest of the computer and the physical harddisk platter that is used for storage. Modern hard disks come with 8 ... the harddisk platter . The disk buffer is used so that both the I O interface and the disk read write ... hard drive performance,1557 14.html ref Where a buffer is large and the throughput of the disk ... and Q&A for Solid State Drives date 2009 05 05 ref See also Page cache Harddisk References reflist Category Computer storage devices Category Harddisk computer storage de Festplattencache simple ... from the disk platter. The disk buffer is physically distinct from and is used differently than the page cache typically kept by the operating system in the computer s main memory . The disk buffer is controlled by the microcontroller in the harddisk drive , and the page cache is controlled by the computer to which that disk is attached. The disk buffer is usually quite small, from 8 ... cache is reused multiple times, the data in the disk buffer is rarely reused. Fact date September 2007 In this sense, the terms disk cache and cache buffer are misnomers the embedded controller s memory is more appropriately called the disk buffer. Note that disk array controller s, as opposed to disk controller s, usually have normal cache memory of around 0.5&ndash 8 GiB. Uses Read ahead read behind When executing a read from the disk, the disk arm moves the Disk read and write head read ... system. The disk s embedded computer typically saves these unrequested sectors in the disk buffer, in case the operating system requests them later. Speed matching The speed of the disk s I O interface ... more details
The term disk space is an amount of computer storage space on random access memory devices, such as on a hard drive , floppy or USB flash drive . Citation needed date September 2011 Disk space units are commonly measured in large numbers of bytes , such as kilobytes , megabytes , and gigabytes , with each unit 1024x times larger than the previous unit. The term originated in the 1950s, for the storage area on a harddisk drive , which internally had disk shaped platters to rotate quickly. As storage devices have been created in other shapes, the term disk space has still been used to refer to areas of permanent storage on various storage devices. The total disk space can span multiple devices, such as areas on an array of disk drives. ref NT Server and Disk Subsystem Performance , Microsoft.com, 2010, webpage http technet.microsoft.com en us library cc767920.aspx MS2 . ref The broader term storage space is so widely used that it can be mistaken for property storage, as with items stored in a closet or storage bin. Hence, the term disk space has remained in use, even when the storage devices are no longer shaped as disks. When storage of data is not permanent, then the common term memory space is often used instead. References Reflist Category Computer memory ... more details
unreferenced date May 2010 The disk controller is the Electronic circuit circuit which enables the Central processing unit CPU to communicate with a harddisk , floppy disk or other kind of disk drive . Early disk controllers were identified by their storage methods and data encoding. They were typically implemented on a separate controller card. Modified frequency modulation MFM controllers were the most common type in small computers, used for both floppy disk and harddisk drives. Run length limited RLL controllers used data compression to increase storage capacity by about 50 . Priam created a proprietary storage algorithm that could double the disk storage. Shugart Associates Systems Interface Shugart Associates System Interface SASI was a predecessor to SCSI . Modern disk controllers are integrated into the disk drive. For example, disks called SCSI disks have built in SCSI controllers. In the past, before most SCSI controller functionality was implemented in a single chip, separate SCSI controllers interfaced disks to the SCSI bus. The most common types of interfaces provided nowadays by disk controllers are Parallel ATA PATA IDE and Serial ATA for home use. High end disks use SCSI , Fibre Channel or Serial Attached SCSI . Disk controller versus host adapter The correct term for the components that allows a computer to talk to a peripheral bus is host adapter or host bus adapter HBA . On the other hand, a disk controller allows a disk to talk to the same bus. Those two are often confused, especially in the Advanced Technology Attachment PC world . In fact signals read by a disk read and write head are converted by a disk controller, then transmitted over the peripheral ..., and then read by the CPU . Sometimes there may be yet another controller between a host adapter and a disk controller a disk array controller that allows RAID Hardware RAID hardware RAID to be formed ... also Disk array controller Floppy disk controller Forensic disk controller Controller computing ... more details
Disk swapping refers to the practice of inserting and removing, or swapping, floppy disks in a floppy disk drive based computer system . In the early days of personal computer s, before hard drives became commonplace, most fully outfitted computer systems had 2 floppy drives addressed as A and B on CP M and MS DOS. Disk drives were expensive, however, and having two was seen as a luxury by many computer users who had to make to with a single drive. The purpose of 2 floppy drives was so that the disk containing the Application software application program could remain in the drive while the data disk containing the user s files could be accessed in the second drive. In order to use a function of the program not loaded into memory, the user would have to first remove the data disk, then insert the program disk. When the user then wanted to save their file, the reverse operation would have to be performed. On some less than user friendly systems, this could result in data loss when, for example, files were saved onto the program disk. Disk swapping was an infamous feature of early Macintosh 128k systems, which were extremely RAM starved. Category Floppy disk computer storage ... more details
Image DOM.JPG thumb right 250px Disk on module A disk on module DOM is a Solid state drive flash drive with either 40 44 pins Parallel ATA IDE Standard ATA Interface USB or SATA Interface to be used as a computer harddisk drive HDD . The flash to IDE converter simulates a harddisk, and therefore the modules can be used without additional software or drivers. They are used particularly within embedded computing systems where they can often be deployed in to very harsh environments where mechanical harddisk drives would simply fail , or in a thin client because of small size, low power consumption and silent operation. DOMs are highly reliable as they do not have any moving parts like regular hard disks and are small in size and light in weight. However, after a disk crash in traditional harddisk, some data may still be recoverable by scanning the physical media using specialized equipment, but there is no known method to recover lost data from a physically damaged DOM. Citation needed date July 2010 Currently storage capacities range from 32MB to 32GB with various form factor including vertical or horizontal orientation. The DOM works the same way as a solid state drive , but it is generally plugged directly to the motherboard. External links History http www.storagesearch.com ssd.html STORAGEsearch.com http www.soarland.com CF Card Adapter catalog 41.html CF to 40 Pin 44 Pin SATA ZIF Adapter DEFAULTSORT Disk On Module Category Solid state computer storage media Compu hardware stub de Disk on Module fr Disk On Module it Disk on module nl Disk on module ru Disk on Module ... more details
from a Floppy disk floppy or Harddisk drive harddisk based on the BIOS . This permits simple disk ... for Microsoft Windows capable of editing and searching in harddisk and logical drives. http www.winhex.com ...A disk editor is a computer program that allows its user to read, edit, and write raw data at ASCII character or hexadecimal , byte byte levels on disk drives e.g., harddisk s, USB flash disk s or removable media such as a floppy disk s as such, they are sometimes called sector editors, since the read write routines built into the electronics of most disk drives require to read write data in chunks of disk sector sector s usually 512 bytes . Many disk editors can also be used to edit the contents of a running computer s computer memory memory or a disk image . Unlike hex editors, which are used to edit Computer file files , a disk editor allows access to the underlying disk structures, such as the master ... directories . Programmers can use disk editors to understand these structures and test whether ... disk editors include special functions which enable more comfortable ways to edit and fix file systems or other disk specific data structures. Furthermore some include simple file browsers that can present the disk contents for partially corrupted file systems or file systems unknown to the operating system. These features can be used for example for file recovery. History Disk editors for home ... resets, instead of having to be re loaded on the same disk drive that later would hold the floppy to be edited the majority of home computer users possessed only one floppy disk drive at that time . Having the disk editor on cartridge also helped the user avoid editing damaging the disk editor application disk by mistake. All disk editors strive to be better than code debug command DEBUG ... and is in essence useless as disk editor for the system drive. The Resource Kit and the support ... Technet accessdate 2011 07 05 ref as a very simple disk editor supporting the use and modification ... more details
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