Information about Block (data Storage)
In computing (specifically data transmission and data storage), block is a sequence of bytes or bits, having a nominal length (a block size). Data thus structured is said to be blocked. The process of putting data into blocks is called blocking. Blocking is used to facilitate the handling of the data-stream by the computer program receiving the data. Blocked data is normally read a whole block at a time. Blocking is almost universally employed when storing data to 9-track magnetic tape, to rotating media such as floppy disks, hard disks, optical discs and to NAND flash memory.
Most file systems are based on a block device, which is a level of abstraction for the hardware responsible for storing and retrieving specified blocks of data, though the block size in file systems block may be multiple of the physical block size. In classical file systems, a single block may only contain a part of a single file. This leads to space inefficiency due to internal fragmentation, since file lengths are often not multiples of block size, and thus the last block of files will remain half-empty. This will create slack space. Some newer file systems attempt to solve this through techniques called block suballocation and tail merging.
Block storage is normally abstracted by a file system or database management system for use by applications and end users. The physical or logical volumes accessed via block I/O may be devices internal to a server, direct attached via SCSI or Fibre Channel, or distant devices accessed via a storage area network (SAN) using a protocol such as iSCSI, or AoE. Database management systems often use their own block I/O for improved performance and recoverability as compared to layering the DBMS on top of a file system.
Most file systems are based on a block device, which is a level of abstraction for the hardware responsible for storing and retrieving specified blocks of data, though the block size in file systems block may be multiple of the physical block size. In classical file systems, a single block may only contain a part of a single file. This leads to space inefficiency due to internal fragmentation, since file lengths are often not multiples of block size, and thus the last block of files will remain half-empty. This will create slack space. Some newer file systems attempt to solve this through techniques called block suballocation and tail merging.
Block storage is normally abstracted by a file system or database management system for use by applications and end users. The physical or logical volumes accessed via block I/O may be devices internal to a server, direct attached via SCSI or Fibre Channel, or distant devices accessed via a storage area network (SAN) using a protocol such as iSCSI, or AoE. Database management systems often use their own block I/O for improved performance and recoverability as compared to layering the DBMS on top of a file system.
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computing is synonymous with counting and calculating. Originally, people that performed these functions were known as computers. Today it refers to a science and technology that deals with the computation and the manipulation of symbols.
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Computer data storage, computer memory, and often casually storage or memory refer to computer components, devices and recording media that retain digital data used for computing for some interval of time.
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byte (pronounced /baɪt/) is a unit of measurement of information storage, most often consisting of eight bits. In many computer architectures it is a unit of memory addressing.
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BIT is an acronym for:
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- Bannari amman Institute of Technology
- Bangalore Institute of Technology
- Beijing Institute of Technology
- Benzisothiazolinone
- Bilateral Investment Treaty
- Bhilai Institute of Technology - Durg
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Magnetic tape is a medium for magnetic recording generally consisting of a thin magnetizable coating on a long and narrow strip of plastic. Nearly all recording tape is of this type, whether used for recording audio or video or for computer data storage.
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Floppy Disk Drive
8 inch, 5 ¼ inch, and 3.5 inch drives
Date Invented: 1969 (8 inch), 1976 (5 ¼ inch), 1983 (3.5 inch)
Invented By: IBM team led by David Noble
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8 inch, 5 ¼ inch, and 3.5 inch drives
Date Invented: 1969 (8 inch), 1976 (5 ¼ inch), 1983 (3.5 inch)
Invented By: IBM team led by David Noble
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Hard disk drive
An IBM hard disk drive with the metal cover removed. The platters are highly reflective.
Date Invented: September 13 1956
Invented By: An IBM team led by Reynold Johnson
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An IBM hard disk drive with the metal cover removed. The platters are highly reflective.
Date Invented: September 13 1956
Invented By: An IBM team led by Reynold Johnson
Connects to:
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optical disc is a flat, circular, usually polycarbonate disc where data is stored in the form of pits (or bumps) within a flat surface, usually along a single spiral groove that covers the entire recorded surface of the disc.
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Flash memory is non-volatile computer memory that can be electrically erased and reprogrammed. It is a technology that is primarily used in memory cards, and USB flash drives (thumb drives, handy drive, memory stick, flash stick, jump drive) for general storage and transfer of data
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file system (often also written as filesystem) is a method for storing and organizing computer files and the data they contain to make it easy to find and access them.
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Abstraction is the process of generalization by reducing the information content of a concept or an observable phenomenon, typically in order to retain only information which is relevant for a particular purpose.
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Hardware is a general term that refers to the physical artifacts of a technology.It may also mean the physical components of a computer system.
Hardware historically meant the metal parts and fittings that were used to make wooden products stronger, more functional, longer
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Hardware historically meant the metal parts and fittings that were used to make wooden products stronger, more functional, longer
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computer file is a block of arbitrary information, or resource for storing information, which is available to a computer program and is usually based on some kind of durable storage.
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In computer storage, Slack space or file slack is the area between the end of a file and the end of the last cluster or sector used by that file. This area is simply wasted storage potential, so file systems that use smaller clusters utilize the disk space more effectively.
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Block suballocation is a feature of some computer file systems which allows large blocks or allocation units to be used while making efficient use of "slack" space at the end of large files, space which would otherwise be lost for other use to internal fragmentation.
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Block suballocation is a feature of some computer file systems which allows large blocks or allocation units to be used while making efficient use of "slack" space at the end of large files, space which would otherwise be lost for other use to internal fragmentation.
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A database management system (DBMS) is computer software designed for the purpose of managing databases. Typical examples of DBMSs include Oracle, DB2, Microsoft Access, Microsoft SQL Server, PostgreSQL, MySQL, FileMaker and Sybase Adaptive Server Enterprise.
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SCSI (Small Computer System Interface) is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces.
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Fibre Channel is a gigabit-speed network technology primarily used for storage networking. Fibre Channel is standardized in the T11 Technical Committee of the InterNational Committee for Information Technology Standards (INCITS), an American National Standards Institute
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In computing, a storage area network (SAN) is an architecture to attach remote computer storage devices (such as disk arrays, tape libraries and optical jukeboxes) to servers in such a way that, to the operating system, the devices appear as locally attached.
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Internet SCSI (iSCSI) is a network protocol standard, officially ratified on 2003-02-11 by the Internet Engineering Task Force, that allows the use of the SCSI protocol over TCP/IP networks. iSCSI is a transport layer protocol in the SCSI-3 specifications framework.
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ATA over Ethernet (AoE) is a network protocol developed by the Brantley Coile Company [1] , designed for accessing ATA storage devices over Ethernet networks. It gives the possibility to build SANs with low-cost, standard technologies.
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block allocation map (BAM) is a data structure used to track the allocated or freed disk blocks.
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See also
- File Allocation Table
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block size. Both the input (plaintext) and output (ciphertext) are the same length; the output cannot be shorter than the input — this is logically required by the Pigeonhole principle and the fact that the cipher must be invertible — and it is simply undesirable for
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sector
(C) Track sector
(D) Cluster]] In the context of computer disk storage, a sector is a sub-division of a track (Figure 1, item A)[1] on a magnetic disk or optical disc. Each sector stores a fixed amount of data.
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(C) Track sector
(D) Cluster]] In the context of computer disk storage, a sector is a sub-division of a track (Figure 1, item A)[1] on a magnetic disk or optical disc. Each sector stores a fixed amount of data.
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