Image Disk structure2.svg thumb Figure 1. Disk structures br A Track br B Geometrical sector br C Track sector br D cluster file system Cluster In computer disk storage, a sector is a subdivision of a Track disk drive track on a magnetic disk or optical disc . Each sector stores a fixed amount of user ... or 2048 bytes for optical discs of user accessible data per sector. Newer hard drives use 4096 byte 4 KB or 4K Advanced Format sectors. Mathematically, the word sector means a portion of a disk ... a slice of a pie. Thus, the disksector Figure 1, item C refers to the intersection of a track and mathematical sector . In hard disk drives, each physical sector is made up of three basic areas, the sector header, the data field and the error correcting code ECC . The sector header contains information ... products to utilize the larger sector format. Citation needed date March 2011 By the end of 2007, Samsung and Toshiba began shipments of 1.8 inch hard disk drives with 4096 byte sectors, the sector size ... transition to 4K as the new standard sector size for all applications using hard disk drives. Under ... head sector Block data storage Disk storage Disk formatting Hard disk drive partitioning File Allocation .... Later the term referring to the data area was replaced by sector, and block became associated with the data ... tt bs bytes tt . This process never changes the actual sector size of a medium only the size of the blocks that dd will manipulate is modified. The standard sector size of 512 bytes for magnetic disks was established with the inception of the hard disk drive in 1956. Through a coordinated effort organized by the industry trade organization, International Disk Drive Equipment and Materials ... the implementation and standards that would govern sector size formats exceeding 512 bytes to accommodate ... later, Specify date March 2011 hard disk drives supporting 1,024 byte sectors began to be integrated ... on storage devices. The movement accelerated in 2010, when three of the five hard disk drive manufacturers ... more details
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 preceded by followed by 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 DEFAULTSORT Disk, The Category 1975 short stories Category Short stories by Jorge Luis Borges story stub es El disco ... 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 hard disk is backed up to another hard disk 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
Wiktionarypar sectorSector may refer to Places Sector, Devon , a location in the county of Devon in south western England Sector, West Virginia , an unincorporated community in Hampshire County, West Virginia, United States of America In computing Cylinder head sector or CHS , an early method for giving addresses to each physical block of data on a hard drive Disksector , a physical subdivision of space on a computer disk storage medium, specifically a subdivision of a track in portal rendering , a convex polygonal segment of map space used to facilitate calculation of the visibility of objects in a computer display Geographic subdivisions Sectors of Guinea Bissau Geometry Circular sector , also known as a pie piece , the portion of a circle enclosed by two radii and an arc Spherical sector , portion of a sphere enclosed by two radii from the center of the sphere. Hyperbolic sector , is a region of the Cartesian plane bounded by rays from the origin to two points a, 1 a and b, 1 b and by the hyperbola xy 1. Fictional uses Sector Star Trek , a fictional area of space designation used in the Star Trek universe for interstellar navigation Sector General , a series of books about an interstellar hospital in Space, written by James White Other uses Sector economic one of several subdivisions in an economic system used for analysis and classification Sector instrument , also known as a proportional compass or military compass , a calculating instrument consisting of two rulers of equal length joined by a hinge Sector lights , one of three areas relative to a shallow water navigational channel United States Coast Guard Sectors , a shore based operational unit of the United States Coast Guard SECTOR , a United States nationwide radio network operated by the U.S. Immigration and Customs Enforcement See also Zone disambiguation Region Area disambig de Sektor es Sector fr Secteur ko it Settore lt Sektorius reik m s nl Sector ja pt Setor ro Sector dezambiguizare ru ... more details
disksector editor for DOS. Freeware. http www.ibiblio.org pub micro pc stuff freedos files util ...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., hard disk 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 disksectorsector 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. List of some disk editors or products containing them External links ... disk editor and RAM editor for Win9x NT and up. http wxhexeditor.sf.net wxHexEditor designed for huge ... program.php?ProgramID 24 Roadkil s Sector Editor A lightweight sector editor which can also ... may need cleanup http apps.tempel.org iBored iBored cross platform block oriented disk and file ... more details
unreferenced date October 2007 A flippy disk sometimes known as a flippy is a Double sided disk double sided 5 floppy disk , specially modified so that the two sides can be used independently but not simultaneously in single sided drives. Use of flippy disks was most common during the 8 bit home computer era of the early to mid 1980s. Generally, there were two levels of modifications For Disk Operating System s that did not use the Hard sectoring index hole in the disk to mark the beginnings of tracks, the flippy modification required only a new write enable notch to be cut. For this purpose, specially designed single square hole hole punchers, commonly known as disk doublers , were produced and sold by third party computer accessory manufacturers. Many users, however, made do with a standard round hole puncher and or an ordinary pair of scissors for this job. For disk operating systems that did use index sync, a second index hole window had to be punched in both sides of the jacket, and for hard sectored formats, an additional window must be punched for the sector holes. While cutting a second notch was relatively safe, cutting additional windows into the jacket was at great peril to the disk within. A number of floppy disk manufacturers produced ready made flippy media. As the cost ... sensors so that the disk could be flipped over without the necessary index hole punch. Data written with these rare drives complicates conversions today for retrocomputing archivists due to the sector .... Two versions on one disk During the time of single sided floppy disks some software manufacturers would use the two sides of one floppy disk to store two different copies of the same program. Each ... II family Apple II or an Atari 8 bit family Atari 8 bit version on the other side of the disk. These releases ... placed on the flip side of the disk. If one put the disk into the drive upside down, the game played ... disk drives Category Legacy hardware ... more details
Disk cloning is the process of copying the contents of one computer hard disk to another disk or to an image file. Often, the contents of the first disk are written to an disk image image computer file file as an intermediate step, and the second disk is loaded with the contents of the image. This procedure is also useful when moving to a larger capacity disk or to restore the disk to a previous state. Uses There are a number of notable uses for disk cloning software. These include Reboot and restore a technique in which the disk of a computer is automatically wiped and restored from a clean , master ... manufacturers and larger companies. Hard drive upgrade An individual user may use disk copying cloning to upgrade to a new, usually larger, hard disk. Full system backup A user may create a comprehensive ... to disk cloning on the x86 platform specific details may not apply to other platforms. To provision the hard disk of a computer without using disk cloning software, the following steps are generally required for each computer Create one or more partition IBM PC partition s on the diskDisk formatting ... driver s for the particular hardware Install application software With disk cloning, this is simplified to Install the first computer, as above. Create an image of the hard disk optional Clone the first disk, or its image, to the remaining computers This can be referred to simply as a recovery disc. History Before Windows 95 , some computer manufacturers used hardware disk copying machines to copy software. This had the disadvantages of copying not just the used data on the disk, but also unused Disksectorsector s, as the hardware used was not aware of the structures on the disks. A larger hard disk could not be copied to a smaller one, and copying a smaller one to a larger left the remaining space on the new disk unused. The two disks required identical geometries. Other manufacturers ... simply to copy all files from one disk to another, because there are special booting boot files or boot ... more details
showing the circular paths traced by the holes in a Nipkow disk A Nipkow disk sometimes Anglicized as Nipkov disk , also known as scanning disk , is a mechanical, geometrically operating image scanning device, invented by Paul Gottlieb Nipkow . This scanning disk was a fundamental component in mechanical ... disk of any suitable material metal, plastic, cardboard, etc. , with a series of equally distanced ... from an external radial point of the disk and proceeding to the center of the disk, much like a gramophone record . The holes, when the disk rotates, trace circular ring surfaces, with inner and outer diameter depending on each hole s position on the disk and thickness equal to each hole s diameter. These surfaces may or may not partly overlap, depending on the exact construction of the disk. Process A lens projects an image of the scene in front of it directly onto the disk. ref cite web url http users.swing.be philippe.jadin nipkowdisk.htm title The Nipkow disk publisher Users.swing.be date ... up as a pattern of light and dark by a sensor. If a light is controlled behind a second Nipkow disk ... it remains no larger than the one projected onto the original receiving disk. When spinning the disk while observing an object through the disk, preferably through a relatively small circular sector of the disk the viewport , for example, an angular quarter or eighth of the disk, the object seems scanned line by line, first by length or height or even diagonally, depending on the exact sector chosen for observation. By spinning the disk rapidly enough, the object seems complete, in a way similar ... understood by covering all of the disk but a small rectangular area with black cardboard which stays fixed , spinning the disk and observing an object through the small area. Here arises one of the drawbacks of the Nipkow disk as an image scanning device the scanlines are not straight lines, but rather curve s. So the ideal Nipkow disk should have either a very large diameter, which means smaller ... more details
boot disk contents. All boot discs must be compatible with the computer they are designed for. MS DOS PC DOS A valid boot sector on the floppy disk, not in the format of a normal disk Computer file ... boot sector on the disk COMMAND.COM KERNEL.SYS Linux A bootloader such as SYSLINUX or GRUB Linux kernel Initial ram disk initrd See also Live CD Boot sector Booting Darik s Boot and Nuke External links http www.boot land.net forums Boot Land Community forum dedicated to Boot Disk research HSW harvard extension schools computer science e 1 understand 2740 creating a boot disk video Creating a Boot Disk Category Booting ar da Bootdisk de Bootf higes Medium fr Disquette de d marrage ko id Boot disk it Disco di avvio ms Cakera but ja pt Disco de boot ...A boot disk is a removable digital data storage medium from which a computer can load and run booting boot an operating system or utility program. The computer must have a built in program which will load and execute a program from a boot disk meeting certain standards. Boot disks are used for Operating system installation. Data recovery . Data remanence Purging Data purging . Hardware or software ... in case of lost password is possible with an appropriate boot disk with some operating systems. Games .... Floppy disk s and CD ROM s are the most common forms of media used, but other media, such as magnetic ... medium, it is usual for the boot program to use some system RAM as a RAM disk for temporary computer ... data floppies could have a virus written to their first sector which silently infect the host computer if switched on with the disk in the drive. Boot floppies Bootable floppies for PCs usually contain MS DOS or miniature versions of Linux . The most commonly available floppy disk can hold only ..., such as CD ROM s or USB flash drives . Booting from a disk A modern PC is configured to attempt ... a selection may be made. Modern Apple computers will boot from an appropriate disk if the user presses ... more details
A disk compression utility software software utility increases the amount of information that can be stored on a hard disk drive of given size. Unlike a file compression utility which compresses only specified files and which requires the user computing user designate the files to be compressed a disk ... information needs to be stored to the hard disk, the utility will data compression compress the information. When information needs to be read, the utility will decompress the information. A disk compression ... software application s access the hard disk using these routines, they continue to work after disk compression has been installed. Disk compression utilities were popular especially in the early 1990s ... rather expensive at the time, costing roughly 10 USD per megabyte. For the users who bought disk ... more disk space as opposed to replacing their current drive with a larger one. A good disk compression utility could, on average, double the available space with negligible speed loss. Disk compression ... to increased capacities and lower prices. Note While the most familiar disk compression utilities ... , for example, worked on the Apple Macintosh platform. Common disk compression utilities Standalone ... from Salient Software Bundled utilities The idea of Bundling marketing bundling disk compression ... compressed drive like those above. How disk compression works Disk compression usually creates ... to how a single physical hard drive can be disk partitioning partitioned into multiple virtual drives ... required changes to the booting boot process as follows BIOS loads sector 0 of the first physical hard drive partition sector Partition sector loads sector 0 of the bootable partition. In this case, it s the host drive. Host drive sector 0 loads in the case of MS DOS IO.SYS and begins Config.Sys processing ..., disk compression could actually increase system performance. This was accomplished two ways Once compressed, there was less data to be stored. Disk accesses would often be batched together for efficiency ... more details
Digital s Advanced Format The 4K Sector Transition Begins ref The earliest disk drives also had fixed block sizes e.g. http www 03.ibm.com ibm history exhibits storage storage 350.html IBM 350 disk ... level formatting of the floppy disk, normally writes 18 Disksectorsector s of 512 byte s to each ... up an empty file system on the disk and, for PC s, installing a boot sector . This is a fast operation ...Image Formatting c drive.JPG thumb Formatting a hard drive using MS DOS Disk formatting is the process for preparing a hard disk drive or flexible disk for its use by an operating system OS , usually including the creation of a file system . For some operating systems, disk formatting may create multiple file systems on the same device by dividing the disk into sections, called Disk partitioning partitions , one for each file system. ref http www.partitionwizard.com help what is disk formatting.html What is disk formatting? ref A variety of application programs exist for disk formatting, pictured ... 791D 1994, AT Attachment Interface for Disk Drives ATA 1 , section 7.1.2 ref drives, appear at their interface ... 03.ibm.com ibm history exhibits storage storage 1301.html title IBM 1301 disk storage unit author ... disk subsystems on the IBM System 360 expanded this concept in the form of Count Key Data CKD and later ... 3390 direct access storage device ref Floppy disk s generally only used fixed block sizes but these sizes were a function of the host s Operating System OS and its interaction with its Floppy disk controller ... sizes depending upon the host OS and controller. Optical disk s generally only use fixed block sizes. Disk formatting process Formatting a disk for use by an operating system and its applications involves ... with markers indicating the start of a recoding block typically today called sector markers and other information to be used later, in normal operations, by the disk controller to read or write data. This is intended to be the permanent foundation of the disk, and is often completed at the factory ... more details
as a single cylinder. DisksectorSector a segment of a track Low level disk format formatting establishing ...Unreferenced date June 2010 Disk storage or disc storage is a general category of storage mechanisms ... on a surface layer deposited of one or more planar, round and rotating platters. A disk drive is a device ... types are the hard disk drive which contain a non removable disc , the floppy disk floppy disk drive and its removable floppy disk , various optical disc drive s and optical disc associated media . CD s and DVD s are optical devices File SixHardDriveFormFactors.jpg thumb Six hard disk drives File Floppy Disk Drives 8 5 3.jpg thumb Three floppy disk drives File Asus CD ROM drive.jpg thumb A CD ROM optical disk drive Background Music al and sound reproduction audio information was originally recorded ... where the data is recorded in a digital format as optical information. The first commercial disk storage device, that is the first commercial digital disk storage device, was the IBM IBM 350 IBM 350 RAMAC 350 shipped in 1956 as a part of the RAMAC IBM 305 RAMAC computing system. Disk storage is now ... innovation in disk storage technology, coupled with less vigorous innovation in tape storage, has reduced the density and cost per bit gap between disk and tape, reducing the importance of tape as a complement to disk. Today disk storage devices typically have a single head that moves across a disk ... Samsung HD753LJ 01 Top.jpg center A typical hard disk drive center Image Samsung HD753LJ 02 Bottom.jpg ... cover removed center Image Hard disk platters and head.jpg center Disks 2 and actuator arms 4 center Image Samsung HD753LJ 05 Head.jpg center The head and disk center Image Hard disk head.jpg center Head on the disk platter center gallery Too HDD specific, putting better images in intro Disk drives are Computer data storage block storage devices . Each disk is divided into logical Block data storage ... block addresses LBA . Read from or writing to disk happens at the granularity of blocks. Originally ... more details
Disk winged may refer to Peter s Disk winged Bat , bat species from South and Central America Spix s Disk winged Bat , bat species from South and Central America disambig ... more details
refimprove date September 2010 Image GParted.png thumb 300px GParted is a popular utility used for disk partitioning Disk partitioning is the act of dividing a hard disk drive into multiple logical storage units referred to as partitions , to treat one physical disk drive as if it were multiple disks. Partitions are also termed slice disk slices for operating systems based on BSD , Solaris operating ..., and manipulate these partitions on the hard disk. Benefits of multiple partitions Prose date March ... system OS and program files from user files. This allows disk image image backup s or disk cloning clones ... X, Microsoft Windows or other operating systems on different partitions of the same hard disk and have ... disk might have an access time of 12 ms at 200 IOPS at a limited queue depth with an average throughput ... on partition table partition tables . The total data storage space of a PC hard disk can be divided ... . Extended partition A hard disk may contain only one extended partition the extended partition can ... on the hard disk that may or may not be visible as drives, such as recovery partitions or partitions ... Logical Disk Manager Disk Management program which allows for the creation, deletion and movement of Windows but not other types of partitions. The Windows 7 Vista Disk Manager is Logical Disk Manager ... systems. Other examples of List of disk partitioning software partition management programs for Windows are Acronis Home products overview Acronis Disk Director , http www.partition tool.com Easeus Partition Master , Norton Ghost , and http perfectdisk.raxco.com Perfect Disk . In some instances ... to use multiple partitions on a disk device. Each partition can be used for a file system ... files disabled thus enhancing security . Performance may be enhanced due to less disk head travel ... can therefore be accommodated. On computers with a single hard disk multi boot systems require multiple partitions on that hard disk. Each OS requires one or more special types of partitions whose ... more details
Unreferenced stub auto yes date December 2009 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 hard disk platter s circular, rigid discs coated with a magnetic data storage device data storage surface . Disk pack is the core component of a hard disk 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 be taken off line and allowed to spin down. Its access door could then be opened and an empty top 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. Examples of a hard disks with removable disk packs are the early IBM disk storage IBM 1311 IBM 1311 , and the Digital Equipment Corporation Digital RP04. gallery File Fotothek df n 10 0000117.jpg Operator 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 ibm history exhibits storage storage 1311.html See also commonscat Removable disk packs disk cartridge , hard disk History history of hard disk DEFAULTSORT Disk Pack ... 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
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 hard disk See hard disk 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
Disk aggregation is the process of combining more than one logical or physical disk drive into a larger logical disk drive. This is done for various reasons creating a single logical disk with a capacity larger than any of the available physical disks providing a simple way to increase disk performance a simple way to implement LUN level storage virtualization See also RAID Storage Virtualization Sources Unreferenced date February 2007 compu storage stub Category Storage virtualization ... more details
Primary sources date July 2008 Infobox software name Disk Utility logo Image Diskutil.png 64px screenshot Image Disk Utility screenshot.png 220px Disk Utility screenshot caption author developer Apple ... license Proprietary software Proprietary 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 ... hard disk 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 this will work ... 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 a zero out data, a 7 ..., merging ref http support.apple.com kb TA24359 Mac OS X How to combine RAID sets in Disk Utility ... 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 RW s and DVD RW DVD RW s checking the Self Monitoring, Analysis, and Reporting Technology S.M.A.R.T status of a hard disk. Disk Utility functions may also be accessed from the Mac OS X Command line interface command line with the diskutil and hdiutil 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, and Disk Utility was used for formatting ... 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 hard disk 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 early IBM disk storage 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
refimprove date March 2011 The Disk Fax was a machine that was used in combination with games for the Family Computer Disk System in Japan. One of the main features of the Disk System is the ability to save data, allowing players to save information such as high score s and other achievements on their game disk. Disk Fax machines could be found in certain stores in Japan during the late 80s early 90s. The Disk Fax machines read save data and send the scores to Nintendo for inclusion on a national scoreboard. Disk Fax machines were used by Nintendo to hold contests in Japan. References http www.atarihq.com tsr fds fds.html tsr s NES archive Family Computer Disk System Nintendo hardware NES Category Nintendo hardware Nintendo stub ... more details
unreferenced date May 2010 The disk controller or hard disk controller is the Electronic circuit circuit which allows the Central processing unit CPU to communicate with a hard disk , 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 hard disk 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 bus, then converted again by the host adapter into the suitable format for the motherboard ... a host adapter and a disk controller a disk array controller that allows RAID Hardware RAID hardware ... different functions. See also Disk array controller Forensic disk controller Controller computing ... more details
other uses2 Disc Unreferenced date December 2009 File CIRCLE 1.svg thumb left A disk is the region bounded by a circle . An open disk is the interior topology interior of the disk excluding the bounding circle, while a closed disk see closed set is the open disk together with the bounding circle. In geometry , a disk also Spelling of disc spelled disc is the region in a plane geometry plane bounded by a circle . A disk is said to be closed or open according to whether or not it contains the circle that constitutes its boundary. In Cartesian coordinates , the open disk of center math a, b math and radius R is given by the formula math D x, y in mathbb R 2 x a 2 y b 2 R 2 math while the closed disk of the same center and radius is given by math overline D x, y in mathbb R 2 x a 2 y b 2 le R 2 . math The area geometry area of a closed or open disk of radius R is R sup 2 sup see pi . The Ball mathematics ball is the disk generalised to metric spaces . However, sometimes disk is used to mean ball . In theoretical physics a disk is a rigid body which is capable of participating in collisions in a two dimensional gas . Usually the disk is considered rigid so that collisions are deemed elastic collision elastic . Geometry File Unit disk rot.svg thumb right The Euclidean disk is Circular symmetry circular symmetrical . Topological notions The open disk and the closed disk are not homeomorphic ... characteristic of a point and therefore also that of a closed or open disk is 1. Every continuous map from the closed disk to itself has at least one fixed point mathematics fixed point we don t require ... . The statement is false for the open disk consider for example math f x,y left frac x sqrt 1 y 2 2 ,y right math which maps every point of the open unit disk to another point of the open unit disk slightly to the right of the given one. See also Unit disk , a disk with radius one Annulus mathematics Disk algebra Lentoid Moment of inertia of a uniform disc DEFAULTSORT Disk Mathematics Category ... more details
Unreferenced stub auto yes date December 2009 Infobox Software name Disk Copy logo Deleted image removed Image Disk Copy.png Disk Copy icon screenshot caption developer Apple Computer latest release version 10.2 operating system System Software 6 , System 7 Macintosh System 7 , Mac OS 8 , Mac OS 9 , Mac OS X v10.0 , Mac OS X v10.1 , Mac OS X v10.2 genre disk image emulator license Disk Copy was the default utility for handling disk image s in System 7 Macintosh System 7 through Mac OS X 10.2 Usable in System Software 6 as well . In later versions of Mac OS X it has been replaced by DiskImageMounter for mounting the images and Disk Utility for creating them. Although the last official public release of Disk Copy for Mac OS 9 was version 6.3.3, there was to be a version 6.5 that supported the newer DMG image format introduced with Mac OS X. But because Apple had stopped support for OS 9 already, support for the old OS was eventually removed in favour of OS X. As such the OS 9 version of 6.5 only ever made it to beta 13 before development on it stopped. There was also a developer version 6.4 that 6.5 was based on and had most of the same functionality, but as a developer version it was never released. Although version 6.4 and 6.5 will read DMG images when the system is booted into OS 9, they can only do so if the image is not compressed. Disk Copy was also the name of an Apple utility distributed with some of the earliest version of the Mac OS. In order to copy 400K floppy disks using as few disk swaps as possible on a machine with only 128K of RAM, the original Disk Copy used the screen buffer to store binary data from the disk being copied as a result, the screen other than ... image formats Disk Copy Disk Copy 4.2 DiskSet PC drive container raw disk image See also DiskImageMounter The Mac OS X 10.3 and later successor. Disk Utility Creates disk images in Mac OS X 10.3 and later. RaWrite and RaWrite2 for MS DOS and Microsoft Windows dd Unix Category Mac OS Category Disk ... more details
with disc buffer. 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 hard disk platter ... a small amount of memory, used to store the bits going to and coming from the disk platter. The disk ... system in the computer s main memory . The disk buffer is controlled by the microcontroller in the hard disk drive , and the page cache is controlled by the computer to which that disk is attached. The disk buffer is usually quite small, from 2 to 32 Mebibyte MiB , and the page cache is generally ... 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. Fact date September 2007 Note that disk array controller s, as opposed to disk controller ... a read from the disk, the disk arm moves the Disk read and write head read write head to or near ..., the first sectors to be read are not the ones that have been requested by the operating 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 to the computer almost never matches the speed at which the bits are transferred to and from the hard disk platter . The disk buffer is used so that both the I O interface and the disk read write head can operate at full speed. Write acceleration The disk s embedded microcontroller may signal the main computer that a disk write is complete immediately after receiving the write data, before the data are actually ... before the data are permanently fixed in the magnetic media, the data will be lost from the disk buffer, and the file system on the disk may be left in an inconsistent state. On some disks, this vulnerable ... more details
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