MICROSOFT Computer Dictionary, Fifth Edition

Microsoft Computer Dictionary, Fifth Edition

network management and administration, as well as hardware solutions in the form of networkbased computers with or without local storage and expansion capability. Acronym: TCO.

touch pad

n. A variety of graphics tablet that uses pressure sensors, rather than the electromagnetics used in more expensive high-resolution tablets, to track the position of a device on its surface. See also absolute pointing device, graphics tablet.

touch screen

n. A computer screen designed or modified to recognize the location of a touch on its surface. By touching the screen, the user can make a selection or move a cursor. The simplest type of touch screen is made up of a grid of sensing lines, which determine the location of a touch by matching vertical and horizontal contacts. Another, more accurate type uses an electrically charged surface and sensors around the outer edges of the screen to detect the amount of electrical disruption and pinpoint exactly where contact has been made. A third type has infrared light-emitting diodes (LEDs) and sensors around the outer edges of the screen. These LEDs and sensors create an invisible infrared grid, which the user’s finger interrupts, in front of the screen. Compare light pen.

touch-sensitive display n. See touch screen.

touch-sensitive tablet n. See touch pad.

touch tone dialing

n. The signaling system used in telephones with touch-tone keypads, in which each digit is associated with two specific frequencies. During dialing, these frequencies—for example, 1336 Hz and 697 Hz for the number 2—are transmitted to the telephone company. Also called: DTMF, Dual Tone Multiple Frequency.

tower

n. A microcomputer system in which the cabinet for the central processing unit (CPU) is tall, narrow, and deep rather than short, wide, and deep. The motherboard is usually vertical, and the disk drives are often perpendicular to the motherboard. A tower cabinet is at least 24 inches tall. See the illustration. See also cabinet, microcomputer, motherboard. Compare minitower.

Microsoft Computer Dictionary, Fifth Edition

Tower.

TP

n. See transaction processing.

TPC

n. See Transaction Processing Council.

TPC-D

n. Acronym for Transaction Processing Council Benchmark D. A benchmark standard that addresses a broad range of decision support applications working with complex data structures. See also Transaction Processing Council.

TPI

n. See tracks per inch.

TP monitor

n. Short for teleprocessing monitor or transaction processing monitor. A program that controls the transfer of data between terminals (or clients) and a mainframe (or one or more servers) so as to provide a consistent environment for one or more online transaction processing (OLTP) applications. A TP monitor may also control the appearance of the screen displays and check input data for proper format. See also client (definition 3), mainframe computer, OLTP, server (definition 1).

trace

vb. To execute a program in such a way that the sequence of statements being executed can be observed. See also debugger, single step.

traceroute

n. A utility that shows the route a packet takes through a network to arrive at a remote host. A traceroute also reports the IP addresses of all intermediate hosts or routers and the time required for the packet to reach each of them. See also IP address, packet.

Microsoft Computer Dictionary, Fifth Edition

track1

n. One of numerous circular data storage areas on a floppy disk or a hard drive, comparable to a groove on a record but not spiral. Tracks, composed of sectors, are recorded on a disk by an operating system during a disk format operation. On other storage media, such as tape, a track runs parallel to the edge of the medium. See the illustration.

Track1. The storage areas on a floppy disk or hard drive.

track2

vb. 1. To follow a path. 2. In data management, to follow the flow of information through a manual or an automated system. 3. In data storage and retrieval, to follow and read from a recording channel on a disk or a magnetic tape. 4. In computer graphics, to cause a displayed symbol, such as a pointer, to match on the screen the movements of a mouse or another pointing device.

trackball

n. A pointing device that consists of a ball resting on two rollers at right angles to each other, which translate the ball’s motion into vertical and horizontal movement on the screen. A trackball also typically has one or more buttons to initiate other actions. A trackball’s housing is stationary; its ball is rolled with the hand. See the illustration. Compare mechanical mouse.

Trackball.

tracked change

n. A mark that shows where a deletion, insertion, or other editing change has been made in a document.

trackpad

n. A pointing device consisting of a small, flat pad that is sensitive to touch. Users move the mouse cursor on screen by touching the trackpad and moving their fingers across the trackpad’s surface. Such devices are most commonly installed on laptop computers. See also pointing device.

tracks per inch

Microsoft Computer Dictionary, Fifth Edition

n. The density with which concentric tracks (data storage rings) are recorded or can be recorded in an inch of radius on a disk. The greater the density (the more tracks per inch), the more information a disk can hold. Acronym: TPI.

tractor feed

n. A method of feeding paper through a printer using pins mounted on rotating belts. The pins engage holes near the edges of continuous-form paper and either push or pull the paper through. See also continuous-form paper. Compare pin feed.

trademark

n. A word, phrase, symbol, or design (or some combination thereof) used to identify a proprietary product, often accompanied by the symbol TM or ®.

trade show

n. A multivendor sales event or exposition that showcases companies’ products. The computer industry has a number of trade shows every year, including COMDEX.

traditional newsgroup hierarchy

n. The seven standard newsgroup categories in Usenet: comp., misc., news., rec., sci., soc., and talk. Newsgroups can be added within the traditional hierarchy only following a formal voting process. See also comp. newsgroups, misc. newsgroups, newsgroup, news. newsgroups, rec. newsgroups, Request for Discussion, sci. newsgroups, soc. newsgroups, talk. newsgroups, Usenet. Compare alt. newsgroups.

traffic

n. The load carried by a communications link or channel.

traffic management n. See ITM.

traffic shaping

n. A technique for allocating bandwidth and preventing packet loss by enforcing prioritization policies on the transmission of data over a network. Also called: bandwidth shaping. See also bandwidth management, bandwidth reservation, token passing.

trailer

n. Information, typically occupying several bytes, at the tail end of a block (section) of transmitted data and often containing a checksum or other error-checking data useful for confirming the accuracy and status of the transmission. See also checksum. Compare header (definition 2).

trailer label

n. 1. A small block of information used in tape processing that marks the end of a file or the end of the tape and that can contain other information, such as the number of records in the file or files on the tape. Compare header label. 2. A label used in communications data frames that follows the data and might contain an end-of-message mark, a checksum, and some synchronization bits.

trailing edge

n. The latter part of an electronic signal. When a digital signal switches from on to off, the transition is the trailing edge of the signal.

train1

n. A sequence of items or events, such as a digital pulse train consisting of transmitted binary signals.

train2

Microsoft Computer Dictionary, Fifth Edition

vb. To teach an end user how to use a software or hardware product.

transaction

n. A discrete activity within a computer system, such as an entry of a customer order or an update of an inventory item. Transactions are usually associated with database management, order entry, and other online systems.

transactional e-mail

n. A form of Web-based marketing in which goods and services are sold to consumers directly from an e-mail message. Unlike traditional e-mail marketing that requires the e-mail recipient to visit the seller’s Web site, transactional e-mail allows an entire sales transaction to be completed from within the marketing e-mail. To take advantage of transactional e-mail buying options, the recipient must view the e-mail message in HTML format.

transaction file

n. A file that contains the details of transactions, such as items and prices on invoices. It is used to update a master database file. See also transaction. Compare master file.

transaction log

n. See change file.

transaction processing

n. A processing method in which transactions are executed immediately after they are received by the system. Acronym: TP. See also transaction. Compare batch processing (definition 3).

Transaction Processing Council

n. A group of hardware and software vendors with the goal of publishing benchmark standards. Acronym: TPC.

transaction processing monitor n. See TP monitor.

Transaction Tracking System n. See TTS (definition 2).

Transact-SQL

n. A query language. Transact-SQL is sophisticated SQL dialect loaded with additional features beyond what is defined in the ANSI SQL 92 Standard. Also called: T-SQL, TSQL.

transceiver

n. Short for transmitter/receiver. A device that can both transmit and receive signals. On LANs (local area networks), a transceiver is the device that connects a computer to the network and that converts signals to and from parallel and serial form.

transceiver cable

n. A cable that is used to connect a host adapter within a computer to a LAN (local area network). See also AUI cable, LAN.

transducer

n. A device that converts one form of energy into another. Electronic transducers either convert electric energy to another form of energy or convert nonelectric to electric energy.

transfer1

n. 1. The movement of data from one location to another. 2. The passing of program control from one portion of code to another.

Microsoft Computer Dictionary, Fifth Edition

transfer2

vb. To move data from one place to another, especially within a single computer. Compare transmit.

transfer rate

n. The rate at which a circuit or a communications channel transfers information from source to destination, as over a network or to and from a disk drive. Transfer rate is measured in units of information per unit of time—for example, bits per second or characters per second—and can be measured either as a raw rate, which is the maximum transfer speed, or as an average rate, which includes gaps between blocks of data as part of the transmission time.

transfer statement

n. A statement in a programming language that transfers the flow of execution to another location in the program. See also branch instruction, CALL statement, GOTO statement, jump instruction.

transfer time

n. The time elapsed between the start of a data transfer operation and its completion.

transform

vb. 1. To change the appearance or format of data without altering its content; that is, to encode information according to predefined rules. 2. In mathematics and computer graphics, to alter the position, size, or nature of an object by moving it to another location (translation), making it larger or smaller (scaling), turning it (rotation), changing its description from one type of coordinate system to another, and so on.

transformer

n. A device used to change the voltage of an alternating current signal or to change the impedance of an alternating current circuit.

transient

adj. 1. Fleeting, temporary, or unpredictable. 2. Of or pertaining to the region of memory used for programs, such as applications, that are read from disk storage and that reside in memory temporarily until they are replaced by other programs. In this context, transient can also refer to the programs themselves. 3. In electronics, of or pertaining to a short-lived, abnormal, and unpredictable increase in power supply, such as a voltage spike or surge. Transient time is the interval during which a change in current or voltage is building up or decaying.

transient suppressor

n. A circuit designed to reduce or eliminate unwanted electrical signals or voltages.

transistor

n. Short for transfer resistor. A solid-state circuit component, usually with three leads, in which a voltage or a current controls the flow of another current. The transistor can serve many functions, including those of amplifier, switch, and oscillator, and is a fundamental component of almost all modern electronics. See the illustration. See also base (definition 3), FET, NPN transistor, PNP transistor.

Microsoft Computer Dictionary, Fifth Edition

Transistor.

transistor-transistor logic

n. A type of bipolar circuit design that utilizes transistors connected to each other either directly or through resistors. Transistor-transistor logic offers high speed and good noise immunity and is used in many digital circuits. A large number of transistor-transistor logic gates can be fabricated on a single integrated circuit. Acronym: TTL.

transitive trust

n. The standard type of trust relationship between Windows domains in a domain tree or forest. When a domain joins an existing forest or domain tree, a transitive trust is automatically established. Transitive trusts are always two-way relationships. This series of trusts, between parent and child domains in a domain tree and between root domains of domain trees in a forest, allows all domains in a forest to trust each other for the purposes of authentication. For example, if domain A trusts domain B and domain B trusts domain C, then domain A trusts domain C. See also domain, forest, one-way trust, two-way trust.

translate

vb. 1. In programming, to convert a program from one language to another. Translation is performed by special programs such as compilers, assemblers, and interpreters. 2. In computer graphics, to move an image in the “space” represented on the display, without turning (rotating) the image.

translated file

n. A file containing data that has been changed from binary (8-bit) format to ASCII (7-bit) format. BinHex and uuencode both translate binary files into ASCII. Such translation is necessary to transmit data through systems (such as e-mail) that may not preserve the eighth bit of each byte. A translated file must be decoded to its binary form before being used. See also BinHex, uuencode.

translator

n. A program that translates one language or data format into another.

transmission channel n. See channel.

Transmission Control Protocol n. See TCP.

Transmission Control Protocol/Internet Protocol n. See TCP/IP.

transmit

vb. To send information over a communications line or a circuit. Computer transmissions can take place in the following ways: asynchronous (variable timing) or synchronous (exact timing); serial (essentially, bit by bit) or parallel (byte by byte; a group of bits at once); duplex or full-duplex

Microsoft Computer Dictionary, Fifth Edition

(simultaneous two-way communication), half-duplex (two-way communication in one direction at a time), or simplex (one-way communication only); and burst (intermittent transmission of blocks of information). Compare transfer2.

Transmit Data n. See TXD.

transmitter

n. Any circuit or electronic device designed to send electrically encoded data to another location.

transparency

n. The quality that defines how much light passes through an object’s pixels. If an object is 100 percent transparent, light passes through it completely and renders the object invisible; in other words, you can see through the object.

transparency scanner n. See scanner.

transparent

adj. 1. In computer use, of, pertaining to, or characteristic of a device, function, or part of a program that works so smoothly and easily that it is invisible to the user. For example, the ability of one application to use files created by another is transparent if the user encounters no difficulty in opening, reading, or using the second program’s files or does not even know the use is occurring. 2. In communications, of, pertaining to, or characteristic of a mode of transmission in which data can include any characters, including device-control characters, without the possibility of misinterpretation by the receiving station. For example, the receiving station will not end a transparent transmission until it receives a character in the data that indicates end of transmission. Thus, there is no danger of the receiving station ending communications prematurely. 3. In computer graphics, of, pertaining to, or characteristic of the lack of color in a particular region of an image so that the background color of the display shows through.

transponder

n. A transceiver in a communications satellite that receives a signal from an earth station and retransmits it on a different frequency to one or more other earth stations.

transportable computer n. See portable computer.

transport layer

n. The fourth of the seven layers in the International Organization for Standardization’s Open Systems Interconnection (OSI) reference model for standardizing computer-to-computer communications. The transport layer is one level above the network layer and is responsible for both quality of service and accurate delivery of information. Among the tasks performed on this layer are error detection and correction. See the illustration. See also ISO/OSI reference model.

Microsoft Computer Dictionary, Fifth Edition

Transport layer.

Transport Layer Security n. See TLS.

transpose1

n. The result of rotating a matrix.

transpose2

vb. 1. To reverse, as the order of the letters h and t in hte, in correcting the spelling of the; or reversing two wires in a circuit. 2. In mathematics and spreadsheets, to rotate a matrix (a rectangular array of numbers) about a diagonal axis.

transputer

n. Short for transistor computer. A complete computer on a single chip, including RAM and an FPU, designed as a building block for parallel computing systems.

trap1

n. See interrupt.

trap2

vb. 1. To intercept an action or event before it occurs, usually in order to do something else. Trapping is commonly used by debuggers to allow interruption of program execution at a given spot. See also interrupt, interrupt handler. 2. To slightly overlap adjacent colors in preparing material for printing. Page layout and prepress programs trap color to prevent gaps between colors caused by minor variations in registration during printing.

trapdoor

n. See back door.

trap handler

n. See interrupt handler.

Trash

n. An icon on the screen in the Macintosh Finder, resembling a garbage can. To delete a file or eject a diskette, the user drags the icon for the file or diskette to the Trash. However, until the user shuts down the system or chooses the menu option “Empty Trash,” a file in the Trash is not actually deleted; the user can retrieve it by double-clicking the Trash icon and dragging the file’s icon out of the resulting window. Compare Recycle Bin.

Microsoft Computer Dictionary, Fifth Edition

traverse

vb. In programming, to access in a particular order all of the nodes of a tree or similar data structure.

tree

n. A data structure containing zero or more nodes that are linked together in a hierarchical fashion. If there are any nodes, one node is the root; each node except the root is the child of one and only one other node; and each node has zero or more nodes as children. See also child (definition 2), graph, leaf, node (definition 3), parent/child (definition 2), root.

tree network

n. A topology for a local area network (LAN) in which one machine is connected to one or more other machines, each of which is connected to one or more others, and so on, so that the structure formed by the network resembles that of a tree. See the illustration. See also bus network, distributed network, ring network, star network, token ring network, topology.

Tree network.

tree search

n. A search procedure performed on a tree data structure. At each step of the search, a tree search is able to determine, by the value in a particular node, which branches of the tree to eliminate, without searching those branches themselves. See also branch (definition 1), tree structure.

tree structure

n. Any structure that has the essential organizational properties of a tree. See also tree.

tree view

n. A hierarchical representation of the folders, files, disk drives, and other resources connected to a computer or network. For example, Windows Explorer uses a tree view to display the resources that are attached to a computer or a network. See also resource.

trellis-coded modulation

n. An enhanced form of quadrature amplitude modulation that is used by modems that operate at or above 9,600 bps (bits per second). Trellis-coded modulation encodes information as unique sets of bits associated with changes in both the phase and amplitude of the carrier, as well as using extra signal points for error-checking bits. Acronym: TCM. See also quadrature amplitude modulation.

trendline

n. A graphic representation of trends in data series, such as a line sloping upward to represent increased sales over a period of months. Trendlines are used for the study of problems of prediction. Also called: regression analysis.