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Computer Terminology
This glossary of computer hardware terms is a list of definitions of terms and concepts related to computer hardware, i.e. the physical and structural components of computers, architectural issues, and peripheral devices. A B C D E F G H I J K L M N O P R S T U V W Z See also *List of computer term etymologies *Glossary of backup terms *Glossary of computer graphics *Glossary of computer science *Glossary of computer software terms * Glossary of ener ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Hardware
Computer hardware includes the physical parts of a computer, such as the computer case, case, central processing unit (CPU), Random-access memory, random access memory (RAM), Computer monitor, monitor, Computer mouse, mouse, Computer keyboard, keyboard, computer data storage, graphics card, sound card, Computer speakers, speakers and motherboard. By contrast, software is the set of instructions that can be stored and run by hardware. Hardware is so-termed because it is "Hardness, hard" or rigid with respect to changes, whereas software is "soft" because it is easy to change. Hardware is typically directed by the software to execute any command or Instruction (computing), instruction. A combination of hardware and software forms a usable computing system, although Digital electronics, other systems exist with only hardware. Von Neumann architecture The template for all modern computers is the Von Neumann architecture, detailed in a First Draft of a Report on the EDVAC, 1945 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TrueNorth
A cognitive computer is a computer that hardwires artificial intelligence and machine-learning algorithms into an integrated circuit (printed circuit board) that closely reproduces the behavior of the human brain. It generally adopts a neuromorphic engineering approach. Synonyms are neuromorphic chip and cognitive chip. An example of an cognitive computer implemented using neural networks and deep learning techniques is IBM's Watson machine. A subsequent development by IBM is the 2014 TrueNorth microchip architecture, which is designed to be closer in structure to the human brain than the von Neumann architecture used in conventional computers. In 2017 Intel also announced its own version of a cognitive chip in "Loihi", which it intended to be available to university and research labs in 2018. Intel, Qualcomm, and others are improving neuromorphic processors steadily, Intel with its Pohoiki Beach and Springs systems. IBM TrueNorth chip TrueNorth was a neuromorphic CMOS integrated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache Hit
In computing, a cache ( ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A ''cache hit'' occurs when the requested data can be found in a cache, while a ''cache miss'' occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs. To be cost-effective and to enable efficient use of data, caches must be relatively small. Nevertheless, caches have proven themselves in many areas of computing, because typical computer applications access data with a high degree of locality of reference. Such access patterns exhibit temporal locality, where data is requested that has been recently requested already, and spatial locality, where d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache Replacement Policy
In computing, cache algorithms (also frequently called cache replacement algorithms or cache replacement policies) are optimizing instructions, or algorithms, that a computer program or a hardware-maintained structure can utilize in order to manage a cache of information stored on the computer. Caching improves performance by keeping recent or often-used data items in memory locations that are faster or computationally cheaper to access than normal memory stores. When the cache is full, the algorithm must choose which items to discard to make room for the new ones. Overview The average memory reference time is : T = m \times T_m + T_h + E where : m = miss ratio = 1 - (hit ratio) : T_m = time to make a main memory access when there is a miss (or, with multi-level cache, average memory reference time for the next-lower cache) : T_h= the latency: the time to reference the cache (should be the same for hits and misses) : E = various secondary effects, such as queuing effects in mult ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allocation (computing)
Allocation may refer to: Computing * Block allocation map * C++ allocators * Delayed allocation * File allocation table * IP address allocation * Memory allocation * No-write allocation (cache) * Register allocation Economics * Asset allocation * Economic system * Market allocation scheme * Resource allocation * Tax allocation district Telecommunication * Call-sign allocation plan * Frequency allocation * Type allocation code Other * Allocution (law), or allocutus, is a formal statement made to the court * Allocation (oil and gas) in hydrocarbon accounting to assign the proper portions of aggregated petroleum and gas flows back to contributing sources * Allocation voting in voting * Location-allocation, used in geographic information systems (GIS) * The allocation of scarce resources in operations research See also * Location (other) A location is a fixed geographical point. Location may also refer to: Arts and entertainment * ''Location'' (EP), a 2005 EP b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache Entries
Cache, caching, or caché may refer to: Places United States * Cache, Idaho, an unincorporated community * Cache, Illinois, an unincorporated community * Cache, Oklahoma, a city in Comanche County * Cache, Utah, Cache County, Utah * Cache County, Utah * Cache Peak (Idaho), a mountain in Castle Rocks State Park Other places * Cache, Aosta, a frazione in Italy * Cache Creek (other), several places Arts, entertainment and media * ''Caché'' (album), a 1993 album by Kirk Whalum * ''Caché'' (film), a 2005 film directed by Michael Haneke Science and technology * Cache (biology) or hoarding, a food storing behavior of animals * Cache (computing), a collection of data duplicating original values stored elsewhere on a computer, usually for easier access * InterSystems Caché, a database management system from InterSystems Other uses * Cache (archaeology), artifacts purposely buried in the ground * Geocaching, an outdoor treasure-hunting game which involves looking for c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache Eviction
A CPU cache is a hardware cache used by the central processing unit (CPU) of a computer to reduce the average cost (time or energy) to access data from the main memory. A cache is a smaller, faster memory, located closer to a processor core, which stores copies of the data from frequently used main memory locations. Most CPUs have a hierarchy of multiple cache levels (L1, L2, often L3, and rarely even L4), with different instruction-specific and data-specific caches at level 1. The cache memory is typically implemented with static random-access memory (SRAM), in modern CPUs by far the largest part of them by chip area, but SRAM is not always used for all levels (of I- or D-cache), or even any level, sometimes some latter or all levels are implemented with eDRAM. Other types of caches exist (that are not counted towards the "cache size" of the most important caches mentioned above), such as the translation lookaside buffer (TLB) which is part of the memory management unit (MMU) wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache Coherency
In computer architecture, cache coherence is the uniformity of shared resource data that ends up stored in multiple local caches. When clients in a system maintain caches of a common memory resource, problems may arise with incoherent data, which is particularly the case with CPUs in a multiprocessing system. In the illustration on the right, consider both the clients have a cached copy of a particular memory block from a previous read. Suppose the client on the bottom updates/changes that memory block, the client on the top could be left with an invalid cache of memory without any notification of the change. Cache coherence is intended to manage such conflicts by maintaining a coherent view of the data values in multiple caches. Overview In a shared memory multiprocessor system with a separate cache memory for each processor, it is possible to have many copies of shared data: one copy in the main memory and one in the local cache of each processor that requested it. When one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cache (computing)
In computing, a cache ( ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A ''cache hit'' occurs when the requested data can be found in a cache, while a ''cache miss'' occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs. To be cost-effective and to enable efficient use of data, caches must be relatively small. Nevertheless, caches have proven themselves in many areas of computing, because typical computer applications access data with a high degree of locality of reference. Such access patterns exhibit temporal locality, where data is requested that has been recently requested already, and spatial locality, where d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bus (computing)
In computer architecture, a bus (shortened form of the Latin '' omnibus'', and historically also called data highway or databus) is a communication system that transfers data between components inside a computer, or between computers. This expression covers all related hardware components (wire, optical fiber, etc.) and software, including communication protocols. Early computer buses were parallel electrical wires with multiple hardware connections, but the term is now used for any physical arrangement that provides the same logical function as a parallel electrical busbar. Modern computer buses can use both parallel and bit serial connections, and can be wired in either a multidrop (electrical parallel) or daisy chain topology, or connected by switched hubs, as in the case of Universal Serial Bus (USB). Background and nomenclature Computer systems generally consist of three main parts: * The central processing unit (CPU) that processes data, * The memory that holds the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD DVD
HD DVD (short for High Definition Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to the standard DVD format. HD DVD employed a blue laser with a shorter wavelength (with the exception of the 3× DVD and HD REC variants), and it stored about 3.2 times as much data per layer as its predecessor (maximum capacity: 15 GB per layer compared to 4.7 GB per layer on a DVD). The format was commercially released in 2006 and fought a protracted format war with rival Blu-ray. On February 19, 2008, Toshiba abandoned the format, announcing it would no longer manufacture HD DVD players and drives. The HD DVD Promotion Group was dissolved on March 28, 2008. The HD DVD physical disc specifications (but not the codecs) were used as the basis for the China Blue High-definition Disc (CBHD) formerly called CH-DVD. History In the lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Format War
A format war is a competition between similar but mutually incompatible technical standards that compete for the same market, such as for data storage devices and recording formats for electronic media. It is often characterized by political and financial influence on content publishers by the developers of the technologies. Developing companies may be characterized as engaging in a format war if they actively oppose or avoid interoperable open-industry technical standards in favor of their own. A format war emergence can be explained because each vendor is trying to exploit cross-side network effects in a two-sided market. There is also a social force to stop a format war: when one of them wins as ''de facto'' standard, it solves a coordination problemEdna Ullmann-Margalit: ''The Emergence of Norms'', Oxford Un. Press, 1977. (or Clarendon Press 1978) for the format users. 1800s * Rail gauge. The Gauge War in Britain pitted the Great Western Railway, which used broad gauge, ag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
