Encyclopedia

Data compaction In telecommunication, data compaction is the reduction of the number of data elements, bandwidth, cost, and time for the generation, transmission, and storage of data without loss of information by eliminating unnecessary redundancy, removing irrelevancy, or using special coding.
Data compression In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. For example, this article could be encoded with fewer bits if one were to accept the convention that the word "compression" be encoded as "comp".
Data compression ratio Data compression ratio is a computer term used to quantify the reduction in data quantity produced by a data compression algorithm. A data compression ratio is much like a physical compression ratio used to measure the physical compression of substances.
Data consistency Data consistency summarizes the validity, accuracy, usability and integrity of related data between applications and across the IT enterprise. This ensures that each user observes a consistent view of the data, including visible changes made by the user's own transactions and transactions of other users or processes.
Data conversion Data conversion is the conversion of one form of computer data to another--the changing of bits from being in one format to a different one, usually for the purpose of application interoperability or of capability of using new features. At the simplest level, data conversion can be exemplified by conversion of a text file from one character encoding to another.
Data corruption Data corruption refers to errors in computer data that occur during transmission or retrieval, introducing unintended changes to the original data. Computer storage and transmission systems use a number of measures to provide data integrity, the lack of errors.
Data counter Data counters are used instead of a program counter by the basic model (non von Neumann) of Reconfigurable Computing systems. According to the Xputer model the data counters are parts of address generators like DMA or GAG units, located in auto-sequencing memory blocks for data.
Data cube In computer programming contexts, a data cube is a three- (or higher) dimensional array of values, commonly used to describe a time series of image data. If the images are in color, then the array is generally four-dimensional, with the dimensions representing image X and Y coordinates, time, and RGB color plane.
Data dredging Data dredging or data fishing is the inappropriate (sometimes deliberately so) search for 'statistically significant' relationships in large quantities of data. This activity was formerly known in the statistical community as data mining, but that term is now in widespread use with an essentially positive meaning, so the pejorative term data dredging is now used instead.
Data drilling Data drilling (also drill-down) refers to any of various operations and transformations on tabular, relational, and multidimensional data. The term has widespread use in various contexts, but is primarily associated with specialized software designed specifically for data analysis.
Data Deficient Data Deficient (DD) is a category applied by the IUCN to a species when the available information is not sufficient for a proper assessment of conservation status to be made. This does not necessarily indicate that the species has not been extensively studied; but it does indicate that little or no information is available on the abundance and distribution of the species.
Data Discman A Data Discman is an electronic book device introduced in 1990 by Sony Corporation. It was marketed (in the United States) to college students and international travelers, but had little success outside of Japan.
Data Distribution Service Data Distribution Service for Real-time Systems (DDS) is a specification of a publish/subscribe middleware for distributed systems created in response to the need to augment CORBA with a data-centric publish-subscribe specification. A few proprietary DDS solutions have been available for several years, until 2004 when the two major DDS vendors, the American Real-Time Innovations and the French Thales teamed up to create the DDS specifications that have been approved by the Object Management Group
Data Documentation Initiative The Data Documentation Initiative (DDI) is an international project to create a standard for information describing social science data. Begun in 1995, the effort brings together data professionals from around the world to develop the standard.
Data Durbar Complex Data Durbar is the tomb of Hazrat Syed Abul Hassan Bin Usman Bin Ali Al-Hajweri, the famous Sufi saint of South Asia, where hundreds of thousands of people come each year to pay their respects and to say their prayers. It is located in Lahore, Punjab, Pakistan.
Data element name A data element name is a name given to a data element in, for example, a data dictionary or metadata registry. In a formal data dictionary, there is often a requirement that no two data elements may have the same name, to allow the data element name to become an identifier, though some data dictionaries may provide ways to qualify the name in some way, for example by the application system or other context in which it occurs.
Data entry clerk A data entry clerk is a member of staff who reads hand-written or printed records and types them into a computer. They are sometimes employed on a temporary basis, but most large companies which have large amounts of data will hire on a near-permanent basis.
Data exchange language Data exchange languages are formal languages specifically designed to support the communication of data and metadata. There are two kinds of data exchange languages: Markup languages and data model based languages.
Data East Data East (データイースト dēta īsuto) was a Japanese video game company, also known as DECO (Data East Corporation, データイースト株式会社 dēta īsuto kabushikigaisha). Their Japanese headquarters were in Tokyo, while their American subsidiary Data East USA was headquartered in San Jose, California.
Data Encryption Standard The Data Encryption Standard (DES) is a cipher (a method for encrypting information) selected as an official Federal Information Processing Standard (FIPS) for the United States in 1976, and which has subsequently enjoyed widespread use internationally. The algorithm was initially controversial, with classified design elements, a relatively short key length, and suspicions about a National Security Agency (NSA) backdoor.
Data Execution Prevention Data Execution Prevention (DEP) is a feature included in modern Microsoft Windows operating systems that is intended to prevent an application or service from executing code from a non-executable memory region. This helps prevent certain exploits that store code via a buffer overflow, for example.
Data file A data file is a computer file which stores data for use by a computer application or system. It generally does not refer to files that contain instructions or code to be executed (typically called program files), or to files which define the operation or structure of an application or system (which include configuration files, directory files, etc.
Data frame In computer networks, a frame is a data packet of fixed or variable length which has been encoded by a data link layer communications protocol for digital transmission over a node-to-node link. Each frame consists of a header frame synchronization and perhaps bit synchronization), payload (useful information, or a packet at higher protocol layer) and trailer.
Data grid A data grid is a grid computing system that deals with data—the controlled sharing and management of large amounts of distributed data. These are often, but not always, combined with computational grid computing systems.
Data General AViiON AViiON was a series of computers from Data General that were the company's main product from the late 1980s until the company's server products were discontinued in 2001. Earlier AViiON models used the Motorola 88000 CPU, but later models moved to an all-Intel solution when Motorola stopped work on the 88000 in the early 1990s.
Data General Business Basic Data General Business Basic was a BASIC interpreter (based on MAI Basic Four's version) developed by Data General for their Nova minicomputer in the 1970s, and later ported to the Data General Eclipse MV and AViiON computers. A majority of applications for the Nova were developed in Business Basic.
Data General Eclipse The Data General Eclipse line of computers by Data General were 16-bit minicomputers released in early 1974 and sold until 1988. The Eclipse was based on many of the same concepts as the Data General Nova, but included support for virtual memory and multitasking more suitable to the small office than the lab.
Data General Nova The Data General Nova was a popular 16-bit minicomputer built by the United States company Data General starting in 1969. The Nova packed enough power to do most simple computing tasks and was packaged into a single rack mount case.
Data haven A data haven is a computer or a network that holds data protected by both technical means (encryption) and location in a country that has either no laws, or poorly-enforced laws against the most common uses of data havens and no extradition treaties. HavenCo (centralized) and Freenet (decentralized) are two models of modern-day data havens.
Data integration Data integration is the problem of combining data residing at different sources and providing the user with a unified view of these data . This important problem emerges in a variety of situations both commercial (when two similar companies need to merge their databases) and scientific (combining research results from different bioinformatics repositories).
Data island A data island is a data store, such as on a PDA or other computing device, that has non-existent or limited external connectivity. This limits the ability of the user to synchronize with or copy the data to other devices.
Data I/O Corporation Data I/O Corporation NASDAQ:DAIO (commonly known as "Data I/O") is a manufacturer of programming and automated device handling systems for programmable integrated circuits. The company is headquartered in Redmond, Washington with sales and engineering offices worldwidehttp://www.
Data link In telecommunication a data link is the means of connecting one location to another for the purpose of transmitting and receiving data. It can also be an assembly, consisting of parts of two data terminal equipments (DTEs) and the interconnecting data circuit, that is controlled by a link protocol enabling data to be transferred from a data source to a data sink.
Data link connection identifier A data link connection identifier (DLCI) is a channel number which is attached to frame relay data frames to tell the network how to route the data. A 13-bit field that defines the destination address of a packet.
Data link layer The data link layer is layer two of the seven-layer OSI model as well as of the five-layer TCP/IP reference model. It responds to service requests from the network layer and issues service requests to the physical layer.
Data Lifeguard Tools Western Digital Data Lifeguard Tools is a computer program for managing hard disks, working under Microsoft Windows and DOS operating systems. It is developed by Kroll Ontrack Inc, distributed by Western Digital Service and Support, and it is free for "non-commercial personal use".
Data Link Provider Interface In the STREAMS computer networking architecture, the Data Link Provider Interface is an interface that a network device driver implements. The interface abstracts away low level details of the hardware and networking protocols, and provides error free delivery of bits over a communications network.
Data management Data management comprises all the disciplines related to managing data as a valuable resource. The official definition provided by DAMA is that "Data Resource Management is the development and execution of architectures, policies, practices and procedures that properly manage the full data lifecycle needs of an enterprise.
Data mart A data mart (DM) is a specialized version of a data warehouse (DW). Like data warehouses, data marts contain a snapshot of operational data that helps business people to strategize based on analyses of past trends and experiences.
Data migration Data migration is the transferring of data between storage types, formats, or computer systems. Data migration is usually performed programmatically to achieve an automated migration, freeing up human resources from tedious tasks.
Data mining Data mining (DM), also called Knowledge-Discovery in Databases (KDD) or Knowledge-Discovery and Data Mining, is the process of automatically searching large volumes of data for patterns using tools such as classification, association rule mining, clustering, etc.. Data mining is a complex topic and has links with multiple core fields such as computer science and adds value to rich seminal computational techniques from statistics, information retrieval, machine learning and pattern recognition.
Data Management Forum The Storage Networking Industry Association’s Data Management Forum (DMF) is a cooperative initiative of IT professionals, integrators and vendors working to define, implement, qualify and teach improved and reliable methods for the protection, retention and lifecycle management of electronic data and information.
Data Mining Extensions Data Mining Extensions (DMX) is a query language for Data Mining Models, much like SQL is a query language for relational databases and MDX is a query language for OLAP databases. DMX syntax is more similar to SQL than MDX.
Data Monitoring Committees A Data Monitoring Committee (DMC, sometimes also called Data Safety Monitoring Board or DSMB) is an independent group of experts who monitor patient safety and treatment efficacy data while a clinical trial is ongoing.
Data path unit In von Neumann type computers the Data path unit (DPU) is the part of the CPU, which executes computation operations and data-stream-driven data transfers from or to the CPU. In addition to the DPU a CPU also has an instruction sequencer including the program counter.
Data point In statistics, a data point is a single typed measurement. Here type is used in a way compatible with datatype in computing; so that the type of measurement can specify whether the measurement results in a Boolean value from {yes, no}, an integer or real number, or some vector or array.
Data Panik data Panik are a Scottish rock band—Steven Clark (Sci-fi Steven), John Clark (John Disco), Amanda MacKinnon (Manda Rin) (all formerly of bis), Stuart Memo (of Multiplies) and Graham Christie (ex Kenickie tour drummer).
Data Position Measurement Data Position Measurement (DPM) is a copy protection method that controls the exact position of data on a CD. Stamped CDs are perfect clones and have the data always at the same position, whereas writable media differ from each other.
Data Processor In data processing or information processing, a Data Processor or Data Processing Unit or Data Processing System is a system which processes data which has been captured and encoded in a format recognizable by the data processing system or has been created and stored by another unit of an information processing system.
Data Protection Act The Data Protection Act (DPA) is a British Act of Parliament that provides a legal basis and allowing for the privacy and protection of data of individuals in the UK. The act places restrictions on organisations which collect or hold data which can identify a living person.
Data Quality Act The Data Quality Act (DQA) passed through the United States Congress in Section 515 of the Treasury and General Government Appropriations Act for Fiscal Year 2001 (). The DQA directs the Office of Management and Budget (OMB) to issue government-wide guidelines that "provide policy and procedural guidance to Federal agencies for ensuring and maximizing the quality, objectivity, utility, and integrity of information (including statistical information) disseminated by Federal agencies".
Data Quality Firewall A Data Quality Firewall is the use of software to protect a computer system from the entry of erroneous, duplicated or poor quality data. Gartner estimates that poor quality data causes failure in up to 50% of CRM systems.
Data reconfiguration and statistical analysis Data reconfiguration and statistical analysis is a poorly regarded managerial function ever since it was widely publicized by Chandler Bing. In the Friends sitcom, the character quit his position as a DRSA manager to pursue a much more creative career in advertising.
Data recovery Data recovery is the process of salvaging data from damaged, failed, wrecked or inaccessible primary storage media when it cannot be accessed normally. Often the data is being salvaged from storage media formats such as hard disk drive, storage tapes, CDs, DVDs, RAID, and other electronics.
Data redundancy In computer storage, data redundancy (sometimes incorrectly referred to as data reliability) is a property of some disk arrays which provides fault tolerance such that if some disks fail, all or part of the data stored by the array is not lost. The cost of providing this feature is most typically increased disk space; implementations require either a duplication of the entire data set or an error-correcting code to be stored on the array.
Data replication Data replication refers to a data storage and backup strategy that copies data from a host computer to another computer, which may or may not be at a remote location. Replication over a computer network can make data backup entirely independent of local data center physical storage.
Data room Data rooms are used in many different types of transaction where the vendor (in the case of a property, M&A or share sale) or the authority (in the case of a PFI/PPP project) wishes to disclose a large amount of confidential data to proposed bidders typically during the due diligence process. The traditional data room will literally be a physically secure continually monitored room, normally in the vendor’s offices (or those of his solicitors), which the bidders and their advisers will visit in order to inspect and report on the various documents and other data made available.
Data Reference Model The Data Reference Model (DRM) is one of the five reference models of the Federal Enterprise Architecture (FEA). The DRM is a framework whose primary purpose is to enable information sharing and reuse across the federal government via the standard description and discovery of common data and the promotion of uniform data management practices.
Data segment A data segment is one of the sections of a program in an object file or in memory, which contains the global variables that are initialized by the programmer. It has a fixed size, since all of the data in this section is set by the programmer before the program is loaded.
Data stream mining Data stream mining is the process of extracting knowledge structures from continuous, rapid data records. Examples of data streams include computer network traffic, phone conversations, ATM transactions, web searches and sensor data.
Data striping The term Data striping refers to the segmentation of logically sequential data, such as a single file, so that segments can be written to multiple physical devices (usually disk drives) in a round-robin fashion.
Data structure diagram A data structure diagram (DSD) is a data model or diagram used to describe conceptual data models by providing graphical notations which document entities and their relationships, and the constraints that binds them. The basic graphic elements of DSDs are boxes, representing entities, and arrows, representing relationships.
Data Solutions Data Solutions represents one and only one institute in Serbia, which provides full research of data recovery technology. The Institute was established after years of developing mechanical and software solutions regarding process of Data Recovery, by the members of CRS project.
Data Storage Server Open-E DSS (Data Storage Server) is an all-in-one IP-Storage solution offering NAS and iSCSI in one single application. DSS is Open-E´s 4th generation of field-proven storage software combining all expertise of the Open-E NAS-XSR Enterprise and Open-E iSCSI Enterprise in one internal USB-DOM (Disk-On-Module).
Data Storage Technology Data Storage Technology (DST) is a 19 mm (3/4") wide magnetic tape data storage format created by Ampex in 1992. It is relatively high capacity and high speed, especially compared to other tape technologies available in the 1990's.
Data Systems & Solutions Data Systems & Solutions LLC is a wholly owned subsidiary of Rolls-Royce plc, with offices in the USA, UK, France and the Czech Republic. It was founded in 1999 as a joint venture between Rolls-Royce plc and Science Applications International Corporation (SAIC).
Data terminal A data terminal, text terminal, or often just terminal (sometimes text console) is a serial computer interface for text entry and display. Original text terminals were electronic computer terminals connected to computers by a serial line, but later computers have built-in system consoles, and terminal emulator programs that work in a graphical desktop environment.
Data terminal equipment DTE is an abbreviation for Data Terminal Equipment, and refers to an end instrument that converts user information into signals for transmission, or reconverts the received signals into user information. A DTE device communicates with the Data Circuit-terminating Equipment (DCE).
Data theft Data theft is a growing problem primarily perpetrated by office workers with access to technology such as desktop computers and hand-held devices, since employees often spend a considerable amount of time developing contacts and confidential and copyrighted information for the company they work for they often feel they have some right to the information and are inclined to copy and/or delete part of it when they leave the company, or misuse it while they are still in employment.
Data type A data type is a constraint placed upon the interpretation of data in a type system in computer programming. Common types of data in programming languages include primitive types (such as integers, floating point numbers or characters), tuples, records, algebraic data types, abstract data types, reference types, classes and function types.
Data Transfer Object Data Transfer Objects (DTO), also known as Value Objects or VO, are a software design pattern used to transfer data between software application subsystems. DTO's are often used in conjunction with Data Access Objects to retrieve data from a database.
Data Transformation Services Data Transformation Services, or DTS, is a set of objects and utilities to allow the automation of extract, transform and load operations to or from a database. The objects are DTS packages and their components, and the utilities are called DTS tools.
Data Transmission Network Data Transmission Network, or DTN, is the brand name for several proprietary technologies for the delivery of financial markets, agricultural, weather, and general news data. Traditionally, DTN has delivered its data by way of dedicated, one-way Ku-Band satellite-based computer terminals, but an Internet-based delivery option is now also offered.
Data Universal Numbering System The Data Universal Numbering System, abbreviated as DUNS or D-U-N-S is a system developed and regulated by Dun & Bradstreet (D&B) which assigns a unique numeric identifier to a single business entity. This numeric identifier is then referred to as a DUNS number.
Data validation In computer science, data validation is the process of ensuring that a program operates on clean, correct and useful data. It uses routines that check for correctness or meaningfulness of data that are input to the system.
Data World Data World is the seventeenth episode of the fourth season for the science fiction television show Sliders. The Sliders arrive at the Chandler Hotel, a constant on most of the parallel Earths they visit, and end up trapped as computer programs within it.
Data's Day Data's Day is a fourth season episode of Star Trek: The Next Generation. Data records the event of a single day of his life, which include Chief O'Brien and Keiko's pre-wedding jitters, learning to dance and investigating the loss of a Vulcan Ambassador in a transporter accident.
Data-directed programming Data-directed programming is a programming paradigm mentioned in Structure and Interpretation of Computer Programs. Although the book goes into extensive detail on its methodology and uses, it is not widely used like many other paradigms.
Data-driven design In computer science, data-driven design is the result of adapting abstract data type design methods to object-oriented programming (Wirfs-Brock & Wilkerson, 1989). This type of design is used in object-oriented programming to define classes during the conception of a piece of software.
Data-flow analysis Data-flow analysis is a technique for gathering information about the possible set of values calculated at various points in a computer program. A program's control flow graph is used to determine those parts of a program to which a particular value assigned to a variable might propagate.
Data-snooping bias In statistics, data-snooping bias is a form of statistical bias generated by the misuse of data mining techniques which can lead to bogus results in scientific research. Although data-snooping biases can occur in any field that uses data mining, data snooping biases are a particular concern in finance and medical research, both of which make heavy use of data mining techniques.
Data-structured language A Data-structured language is a programming language in which the data structure is a main organizing principle, representation, model, for data and logic (code) alike, in which both are stored and operated upon, i.e.
Data: URI scheme The data: URI scheme defined in IETF standard RFC 2397, is an URI scheme that allows inclusion of small data items inline, as if they were being referenced to as an external resource. They tend to be far simpler than alternative inclusion methods, such as MIME with cid: or mid:.
Database The term or expression database originated within the computer industry. Although its meaning has been broadened by popular use, even to include non-electronic databases, this article takes a more technical perspective towards the topic.
Database abstraction layer A database abstraction layer is an application programming interface which unifies the communication between a computer application and databases such as MySQL, Oracle or SQLite. Traditionally, all database vendors provide their own interface tailored to their products which leaves it to the application programmer to implement code for all database interfaces he would like to support.
Database as an IPC In computer programming, Database as an IPC is a term used for the inappropriate use of a database to communicate information between processes. It is an Anti-pattern where a database is used to communicate information between processes on one or more computers.
Database Administration & Automation Database administration refers to the function of managing and maintaining DBMS (database management systems) software. Mainstream DBMS software such as Oracle, IBM DB2 and Microsoft SQL Server need ongoing management.
Database consistency In database systems, a consistent transaction is one that does not violate any integrity constraints during its execution. If a transaction leaves the database in an illegal state, it is aborted and an error is reported.
Database Connection A Database Connection is the method in computer science that allows client software to talk to database server software, whether these exist on the same machine or not. A connection is required to send commands and receive answers, usually in the form of a result set.
Database design Database design is the process of producing a detailed data model of a database. This model contains all the needed logical and physical design choices and physical storage parameters needed to generate a design in a Data Definition Language, which can then be used to create a database.
Database dump A database dump contains a record of the table structure and/or the data from a database and is usually in the form of a list of SQL queries. A database dump is most often used for backing up a database so that its contents can be restored in the event of data loss.
Database engine A database engine is the underlying component that a Database Management System (DBMS) uses to create, retrieve, update and delete (CRUD) data from a database. One may command the database engine via the DBMS's own user interface, and sometimes through a network port.
Database Forensics Database Forensics is a computer science term to refer to the forensic study of databases. Computer Forensics as applied to Operating System files has been well investigated and these principles can be applied to the virtual file system of a Relational Database and the RDBMS software that supports it.
Database machine A database machine or back end processor is a computer or special hardware that stores and retrieves data from a database. It is specially designed for database access and is coupled to the main (front-end) computer(s) by a high-speed channel.
Database marketing Database marketing is a form of direct marketing using databases of customers or potential customers to generate personalized communications in order to promote a product or service for marketing purposes. The method of communication can be any addressable medium, as in direct marketing.
Database normalization Normalization is a process for designing information structures well suited for digital storage. As the capability to store records in digital format has evolved, so too has the science of determining how best to organize the data for upkeep, processing or analysis.
Database of Recorded American Music A joint venture by New World Records and New York University, the Database of Recorded American Music (DRAM) is designed to facilitate the music research of scholars and students by offering on-demand, streaming access to an extensive and ever-growing catalog of essential music. As of 2006, New World Records plans to launch its online subscription service for colleges and universities, an initiative funded by the Mellon and Robert Sterling Clark Foundations.
Database publishing Database Publishing is a term used in the area of automated media production to indicate techniques to automatically make up publications starting from data residing in traditional databases. Common examples are the making up of pricelists and catalogues.
Database security Database Security is the system, processes, and procedures that protect a database from unintended activity. Unintended activity can be categorized as authorized misuse, malicious attacks or inadvertent mistakes made by authorized individuals or processes.
Database server A database server is a computer program that provides database services to other computer programs or computers, as defined by the client-server model. The term may also refer to a computer dedicated to running such a program.

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