64QAM - 64-state quadrature amplitude modulation

DLL dynamic link library DLL libraries do all kinds of things, from holding icons (Windows 3.1's moricons.dll) to enabling Visual Basic programs (vbrun3.dll) to creating network sockets that allow you to hook up to the Internet (winsock.dll).

DMA direct memory access Hardware devices attached to PCs can be designed to send their instructions to and from main memory in one of two ways.

DMD Digital micromirror device A display system under development by Texas Instruments. It involves tiny mirrors that change shape and color as electricity passes through them.

DMI Desktop Management Interface DMI provides a more efficient means of reporting system problems.

DN directory number used to track billing on the ISDN line and corresponds to the number that gets called in establishing a connection.

DNS domain name system the conventions for naming hosts and the way the names are handled across the Internet.

Dolby Pro Logic The analog version of surround sound for home video.

DOM Document Object Model The DOM is a specification under development by the W3C. It will allow all elements of a Web page--graphics, text, headlines, styles, and so on--to be manipulated and acted on by programs and scripting languages

dongle  A device that prevents the unauthorized use of hardware or software.

dot pitch In monitors, the dot pitch is the distance (measured in millimeters) between the holes in the shadow mask

double buffering This programming technique uses two buffers to speed up any computer task when the hardware can process and push information around at the same time.

dpi
dots per inch A measure of resolution in printers and scanners, dpi ratings describe how many pixels such devices can fit into an inch of space.

DQPSK
differential quadrature phase shift keying                DQPSK is a digital modulation technique commonly used with cellular systems.

DRAM
dynamic RAM DRAM is the Hershey's chocolate of readable/writable memory:

dropout  Dropout describes brief pauses in sound in Web-phone and other communications connections as data is lost somewhere on the wire.

DSL digital subscriber line  Digital subscriber lines carry data at high speeds over standard copper telephone wires. With DSL, data can be delivered at a rate of 1.5 mbps (around 30 times faster than through a 56-kbps modem

DSP digital signal processor  A special-purpose microprocessor designed to handle signal-processing applications very quickly.

DSVD digital simultaneous voice/data  DSVD is a communications protocol that allows both voice and data to be transmitted and received at the same time, over a single connection.

DTS A digital surround-sound format used both in home audio and movie theaters.

dual scan  To create a better picture than those on early passive-matrix, flat-panel displays, companies began splitting the screen into two parts and refreshing each simultaneously.

DVD digital versatile disc Originally referred to as digital video discs, these high-capacity optical discs are now used to store everything from massive computer applications to full-length movies. While similar in physical size and appearance to a compact disc or a CD-ROM, DVD is a huge leap from its predecessor's 650MB of storage. A standard single-layer, single-sided DVD can store a whopping 4.7GB of data. But it doesn't stop there--DVD also has a two-layer standard that boosts the single-sided capacity to 8.5GB. And there's more! DVDs can be double-sided, ramping up the maximum storage on a single disc to 17GB. Unfortunately, to use DVDs, you'll have to buy a new drive, but that new hardware will also read your older CD-ROMs and audio CDs.

dynamic bandwidth allocation Using dynamic bandwidth allocation, an ISDN line can handle voice and data at the same time. This way, a person downloading files from the Net could be yakking away on the phone over the same ISDN line.

dynamic voice override ISDN devices that support dynamic voice override will automatically drop and reallocate one of the channels for a voice (phone) call when the handset of the phone is picked up to make a call or when the phone call is received.

E

Easter egg - Easter eggs are also "hidden features" placed by programmers in software applications, operating systems, and even some hardware.

ECP                                                                                                                                   Extended Capabilities Port Microsoft and Hewlett-Packard developed the ECP specification to extend the speed of the humble parallel port and to provide two-way throughput.

EDO RAM
extended data-out RAM This form of dynamic RAM speeds access to memory locations by working on a simple assumption: the next time memory is accessed, it will be at a contiguous address in a contiguous chunk of hardware.

EEPROM
electrically erasable programmable ROMWith EEPROMs, a program tells the chip's controller to give it electronic amnesia and then downloads the new BIOS code into it.

EIDE                                                                                                                                enhanced integrated device (or drive) electronics EIDE gives SCSI-2 a run for its money, and while most people agree that SCSI-2 is technically superior, EIDE is cheaper to implement, which gained it widespread acceptance.

EISA bus
Enhanced Industry-Standard Architecture bus A 32-bit bus for PCs built around 386, 486, or Pentium chips.

electron gun the electron guns sweep across the screen, their strength varying so that a colored image is drawn.

email
electronic mail can send email in several ways--across a local area network, via the Internet, or through an online service like CompuServe or America Online--and can send it to a single recipient or to a whole slew of them.

Emoticon                                                           The trouble with online chat, postings, and email is that anything said in them is open to misinterpretation.

encryption  Encryption is the process of changing data into a form that can be read only by the intended receiver.

EPP
Enhanced Parallel Port EPP spec builds on the design of the humble parallel port, adding two-way communications and faster exchange.

EPROM
erasable programmable ROM Unlike dynamic and static RAM, EPROM chips do not require power to retain their data. Consequently, EPROM chips are commonly used to store BIOS information and basic software for modems, video cards, and other peripherals.

EPS
Encapsulated PostScript An extension of Adobe System's PostScript graphics file format.

Ethernet  Ethernet is a standard for connecting computers into a local area network (LAN).

event handler an event handler is a mechanism for causing a script to react to an event.

Extranet Companies often use extranets to provide nonpublic information to a select group of people, such as business partners or customers.

F

FAQs
frequently asked questionsThese text files are supposed to answer all the questions a newcomer to an online site might have.

fast Ethernet Fast Ethernet is an upgraded standard for connecting computers into a local area network (LAN).

FAT
file allocation table the FAT looks up the locations of all the clusters where the data is stored. The cluster size depends on the size of the hard disk, with bigger drives using bigger clusters.

fat binary it means that the program is a little larger than a regular app.

FCC
Federal Communications Commission The government agency responsible for regulating telecommunications in the United States.

FED
Field emission display These displays work similarly to traditional CRT displays, except each pixel in a FED has its own electron source,

fiber-optic cable Fiber-optic cables consist of thin filaments of glass (or other transparent materials),

file extensionIn filenames, the group of letters after the period is called the file extension. For example, if the filename is command.com, the extension is .com.

filters filters can be used to manage incoming and stored mail.

finger Finger is a program that you point at the username of someone on a networked system.

Firewall This could be a dedicated computer equipped with security measures such as a dial-back feature, or it could be software-based protection called defensive coding.

Flame Flaming is a vitriolic personal attack on another individual--and when a flamer is flamed back, the exchange is called a flame war.

flash ROM This jargon refers to ROM chips that can be reprogrammed with new BIOS instructions after the chips have left the factory. Such ROM chips are technically called EEPROMs.

FlashPix FlashPix is a sophisticated and promising technology, it is not yet an established standard, and its role on the Internet is still unclear.

flat-panel displayAny of a variety of ultrathin displays commonly used for notebook computers.

flat shading The simplest kind of shading is flat shading, which simply fills the polygons with one color.

floating-point math Floating-point is a branch of mathematics often used in spreadsheet operations, and floating-point operations (called FLOPs) can be used to measure computing performance.

FM synthesis
frequency modulation synthesis FM synthesis uses a signal to modulate the frequency of another signal, and the results sound like arcade games from the 1970s or one of the first wave of poker-faced European techno-bands.

focus A monitor's focus is its ability to display sharp images, which are characterized by easy-to-read text; images that are out of focus appear blurry.

Fog In 3D graphics, the fog setting does pretty much what you'd expect...it adds a graduated opacity to areas of the image to simulate fog.

FPU
floating-point unit the FPU can be either a separate chip (such as Intel's 80387 or Motorola's 68881), or it can be integrated into the CPU, such as the Pentium or 68040 processors.

frame buffer The memory on a graphics card that stores information not being displayed onscreen is called a frame buffer.

freeware  Freeware is software you can download, pass around, and distribute without payment.

Frequency measure the frequency of these waves by determining how many of them pass a specific point in a given amount of time. This frequency is often given in cycles per second, or Hertz

frequency spectrum  A frequency spectrum refers to a range of frequencies. For example, cable television commonly occupies the 5-MHz to 550-MHz frequency spectrum.

FTP
file transfer protocol This Internet protocol is used to copy files between computers--usually a client and an archive site.

full duplex  A redundant way of saying duplex, so that it's not confused with half duplex.

full ringing support An ISDN device with full ringing support enables phones, fax machines, and other POTS (plain old telephone service) devices to use ISDN just like an analog phone line.

FYI
for your informationAn acronym often used in email, posting, and chat, this term rarely adds much to the information that follows it, and can be interpreted as snide.

G

gateway A gateway is a program or piece of hardware that passes data between networks.

GDI
graphics device(display) interface The graphics display interface, or GDI, is the part that draws all the graphical objects--including common elements such as scroll bars and lines--to the screen. GDI functions are handled by a program called gdi.exe that loads automatically when you start Windows.

grin, duck, and runthis is used to show emotions in online postings or chat--in this case, to show that a preceding comment should be interpreted as the kind of cheekiness that provokes a good-natured whack upside the head.

ghosting In monitors, shadows and streaking due to drastic changes in onscreen intensity are referred to as ghosting. It is common to see white or black shadows to the right of a solid bar drawn on the screen.

GIF
graphics interchange format Most color images and backgrounds on the Web are GIF files. This compact file format is ideal for graphics that use only a few colors, and it was once the most popular format for online color photos.

gigabyte This year's minimum hard disk size is one gigabyte, or 1,073,741,824 bytes, which should be enough for Windows 95 and other modern operating systems--for a few months at least. Abbreviated as GB.

GNUGNU, which stands for GNU's not Unix, is a system for producing and distributing free software that's upwardly compatible with Unix.

Gopher Gopher is a text-based information retrieval system for the Internet. Equipped with a Gopher client, you can use Gopher servers to search databases around the globe for keywords or subjects.

Gouraud shading Gouraud shading is a complex process using algorithms to create a color gradient.

GPS
Global Positioning System The Global Positioning System is a satellite navigation system used to determine terestrial position, velocity, and time.

Green Book Green Book is the compact disc standard created by Sony and Philips to work on CD-I players.

Grep Unix shorthand for "get regular expression."

GSM
Groupe Speciale Mobile
(Global System for Mobile Communications) This set of standards is widely used in Europe for cellular communications. The audio encoding subset of the GSM standard is best known to computer users because its data compression and decompression techniques are also being used for Web-phone communication and encoding WAV and AIFF files.

GUI
graphical user interface A graphical user interface lets users interact with their computer via icons and a pointer instead of by typing in text at a command line.

GZIP
GNU ZIP  A VRML file compression format similar to ZIP compression.

H

HAL hardware abstraction layerA hardware abstraction layer is a component of an operating system that functions something like an API.

half duplex modem communication was either asychronous full duplex (one character at a time sent in both directions at once) or synchronous half duplex (a block of characters at a time, but sent in only one direction).

handoffThe process of transferring a phone call in progress from one cell transmitter to another cell transmitter that's using a different frequency--without interrupting service.

HDTV
High-definition television A TV signal that offers a much higher resolution and wider aspect ratio than tradition a NTSC signals. It can also refer to the televisions that pick up these signals.

head end A head end is the originating point of a signal in a cable television system.

head-end controller To provide access to the Internet over a cable network, a head-end controller device connects to an IP router that sends and receives the data from the rest of the Internet.

helper applications The only type of media a Web browser absolutely has to handle is hypertext.

Hexadecimal hexadecimal notation uses a base of sixteen: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, A, B, C, D, E, F. While such a system may seem confusing at first, it works extremely well in computing environments.

HFC network
hybrid fiber-coax network HFC networks combine both optical-fiber and coaxial cable lines. Optical fiber runs from the cable head end to neighborhoods of 500 to 2,000 subscribers. Coaxial cable runs from the optical-fiber feeders to each subscriber.

history list a history list is actually a drop-down menu in a Web browser that contains a log of the latest document titles and URLs you have visited during your Web session.

Hit a hit can refer to any one of a few different things. If you perform a search using Excite or SHAREWARE.COM, the results are called hits.

home page Web sites are by nature tangled groups of interconnected pages. To make them easier to navigate, the sites have one or more home pages that you can use for orientation. A home page serves as the site's introduction, starting point, and guide.

HS
high speed  This modem indicator light tells you the modem is prepared to transfer at its maximum capacity. Since it's almost always prepared to do this, it's really useful only for showing that your modem is turned on.

HTTP
hypertext transfer protocol The protocol used to transmit and receive all data over the World Wide Web.

Hub This chunk of hardware is used to network computers together (usually over an Ethernet connection). It serves as a common wiring point so that information can flow through one central location to any other computer on the network.

Heuristics A method of analyzing outcome through comparison to previously recognized patterns. For example, an antivirus program, familiar with behaviors typical of viruses (such as deleting files in sequence), could use heuristics to identify unknown virus strains by their behavior.

hyperlink  Hyperlinks are the easy-to-spot underlined words or phrases you click in World Wide Web documents to jump to another screen or page. Hyperlinks contain HTML-coded references that point to other Web pages, which your browser then jumps to. Also called anchors.

hypermedia  One step ahead of hypertext, hypermedia integrates text, images, video, and sound into its documents. The elements of hypermedia documents are linked in an interactive way. The best way to describe hypermedia is by example--and the most common examples are the sound-laden pages of the World Wide Web.

hypertext  Hypertext is a nonsequential way of presenting information. Hypertext links information in a complex web of associations, powered by hyperlinks. Essentially a way of browsing information, hypertext is a way to describe how you learn information from a well-designed CD-ROM encyclopedia or from the World Wide Web.

I

IDE
integrated device (or drive) electronics This hard-drive interface has all of its controller electronics integrated into the drive itself. The IDE specification handles hard disks up to 504MB in size. Because of its simple instruction set and the short route between controller and drive, it's a quick and easy type of drive to use (unlike SCSI drives and the older Enhanced Small Device Interface (ESDI) drives from the late 1980s). But because it's a limited specification, IDE is gradually being superseded by an enhanced version, EIDE.

IEEE
Institute of Electrical and Electronics Engineers This nonprofit U.S. engineering organization develops, defines, and reviews standards within the electronics and computer science industries.

IMAP
Internet Message Access ProtocolIMAP provides a means of managing email messages on a remote server, similar to the POP protocol. But IMAP offers more options than POP, including the ability to download only message headers, create multiuser mailboxes, and build server-based storage folders.

IMHO
in my humble opinion
(or in my honest opinion) An acronym often used in email, posting, and chat directly before an opinion that may be honest but is rarely humble.

IMO
in my opinion An acronym often used in email, posting, and chat, this is usually more accurate than the alternative IMHO.

in-band signaling ISDN normally uses a separate wire called the D channel to set up calls and handle their signals. In some locations, this third wire isn't available, and bandwidth must be "borrowed" from the other two data-carrying B channels.

information superhighway This is a buzzword from a speech by Al Gore that refers to the Clinton/Gore administration's plan to deregulate communication services and thus widen the scope of the Internet by opening carriers, such as television cable, to data communication.

ink jet printer  Unlike daisy wheel and dot matrix printers, which rely on physical contact with the an inked ribbon and paper, ink jet printers simply spray ink in a series of dots to form characters.

in-line graphic  A fancy way of referring to a graphic image displayed within text--usually in a Web page or a document created in a desktop publishing program.

Interlaced When you watch television, you're looking at an interlaced video display. On TVs as on computer monitors, the whole screen is drawn line by line. But because early television tubes couldn't draw the whole screen before the top began to fade, TV engineers implemented a system called interlacing, which skips every second line on the first pass and fills in those lines on a second pass. 

Internet  The Internet originated in 1969, in the midst of the Cold War, as a "nuke-proof" communications network. As you might guess, it received most of its early financing from the U.S. defense department. Now, however, it consists of countless networks and computers across the world that allow millions of people to share information. The lines that carry the majority of the information are know as the Internet backbone. While the government used to run things, now major Internet service providers (ISPs) such as MCI, GTE, Sprint, UUNET, and ANS own portions of the backbone--a good thing as they have the motivation and the revenue to maintain the quality of these large networks.

Internet backbone This superfast network spanning the world from one major metropolitan area to another is provided by a handful of national Internet service providers (ISPs). These organizations (including Net 99 and Alternet) use connections running at approximately 45 mbps (T3 lines) linked up at specified interconnection points called national access points (which are located in major metropolitan areas). Local ISPs connect to this backbone through routers so that data can be carried though the backbone to its destination.

InterNIC  The InterNIC organization was formed in 1993 to handle domain name registrations. While Network Solutions manages the group, the National Science Foundation, AT&T, and General Atomics also play a part in how the organization is run. InterNIC also maintains a database of domain names, so you can search to see if the one you want is available.

intranet  A play on the word Internet, an intranet is a restricted-access network that works like the Web, but isn't on it. Usually owned and managed by a corporation, an intranet enables a company to share its resources with its employees without confidential information being made available to everyone with Internet access.

I/O port
input/output port  Any socket in the back of a computer that you use to connect to another piece of hardware is called an I/O port.

IP
Internet protocol The Internet protocol defines how information gets passed between systems across the Internet.

IP address
Internet protocol address  This address is a unique string of numbers that identifies a computer on the Internet. These numbers are usually shown in groups separated by periods, like this: 123.123.23.2. All resources on the Internet must have an IP address--or else they're not on the Internet at all.

IP packet  An IP packet is a chunk of data transferred over the Internet using standard Internet protocol (IP). Each packet begins with a header containing addressing and system control information. Unlike uniform ATM "cells," IP packets vary in length depending on the data being transmitted.

IPX
Internetwork Packet Exchange  NetWare's network-layer protocol handles networking addressing, routing, and packets. The most common of all networking protocols, IPX loads when you log on to a network.

IRC
Internet Relay Chat  IRC is a way of hooking up with other Net users to exchange written comments--live and in real time. To do this, you need an IRC client and an IRC server. Once connected to the server, you join a channel, or discussion group, which can include people from all over the world. IRC channels may hold discussions about anything under the sun (and some topics that shouldn't see the light of day).

IrDA
infrared data association  IrDA's goal is to establish standards for the exchange of data over infrared waves. Infrared technology would let devices "beam" information to each other in the same way that your remote control tells the TV to change the channel.

IRQ
interrupt request  an IRQ is a signal from a piece of hardware (such as a keyboard or sound card) indicating that it needs the CPU to do something.

ISAPI
Internet Server Application Program Interface This application programming interface, created by Process Software and Microsoft, is (obviously) tailored to Internet servers.

ISA
Industry Standard Architecture  Pronounced like Mr. Scott saying "Aye, sir" to Captain Kirk, ISA is the bus design that has been used in most PCs since IBM released the PC/AT more than a decade ago. It's a limited 8-bit and 16-bit bus, but it's so widely compatible that it has outlasted technologically superior--and much faster--bus standards like PCI.

ISDN
Integrated Services Digital Network  The plain old telephone system doesn't handle large quantities of data, and the phone companies realized this a long time ago. So the ISDN spec was hammered out in 1984 to allow for wide-bandwidth digital transmission using the public switched telephone network. Under ISDN, a phone call can transfer 64 kilobits of digital data per second. But it's not always easy to adopt.

ISP
Internet service provider  Once upon a time, you could only connect to the Internet if you belonged to a major university or had a note from the Pentagon. Not anymore: ISPs have arrived to act as your (ideally) user-friendly front end to all that the Internet offers. Most ISPs have a network of servers (mail, news, Web, and the like), routers, and modems attached to a permanent, high-speed Internet "backbone" connection. Subscribers can then dial into the local network to gain Internet access--without having to maintain servers, file for domain names, or learn Unix.

ITU-T
International Telecommunications Union-Telecommunication  The newer name for the international committee CCITT, ITU-T has a long way to go until it's as well known as its older counterpart.

J

Jaggy This slang terms refers to the stepping effect you see along curves in onscreen text or in bit-mapped graphics.

JAR
Java Archive  Sun developed the JAR format to store compressed Java applets. Netscape Navigator can download JAR files and save them onto the local hard drive, so that the next time you access the applet it won't have to download it again.

Java  Sun Microsystems' Java is a programming language for adding animation and other action to Web sites.

JavaBeans  A component technology for Java that lets developers create reusable software objects. These objects can be shared--a database vendor can create a JavaBean to support its software, and other developers can easily drop the Bean into their own projects.

JavaScript  Designed by Sun Microsystems and Netscape as an easy-to-use adjunct to the Java programming language, JavaScript code can be added to standard HTML pages to create interactive documents. As a result, JavaScript has found considerable use in the creation of interactive Web-based forms.

Java Virtual Machine  The Java Virtual Machine (VM) is a program that interprets Java bytecodes into machine code. The VM is what makes Java portable--a vendor such as Microsoft or Sun writes a Java VM for their operating system, and any Java program can run on that VM.

JDBC  Java database connectivity. Similar to ODBC, this set of application programming interfaces (APIs) provides a standard mechanism to allow Java applets access to a database.

JIT
just-in-time compiler  When dealing with Java, a just-in-time compiler converts Java bytecode (compiled Java source language statements) into native code designed to run on a specific hardware and operating system platform.

JPEG
Joint Photographic Experts Group This file format for color-rich images was developed by the Joint Photographic Experts Group committee. JPEG compresses graphics of photographic color depth better than competing file formats like GIF, and it retains a high degree of color fidelity. This makes JPEG files smaller and therefore quicker to download..

Jumper An on/off switch used to alter hardware configurations. A jumper is made of wires and a small metal piece that can connect the wires to turn the jumper on.

jukebox  While early jukeboxes swallowed nickels and played the latest singles to make teens tap their toes, modern jukeboxes--at least those used with computers--are designed to provide quick access to multiple CD-ROMs. Jukeboxes range from simple internal drives that hold a quartet of discs to massive external systems capable of holding hundreds of discs.

JVM
Java Virtual Machine  A JVM acts as an interpreter between the Java bytecode and a computer's operating system. Using a JVM, you can run Java code on any number of different computer platforms, including Macintosh, Windows 95, and Unix. JVMs read and execute Java statements one at a time, however, so they are often slower than a just-in-time compiler.

K

kiosk  If the button bars, the menus, and the URL window on your browser leave too little room for the Web page you're trying to look at, it's time for kiosk mode.

kbps  Your modem's speed is measured in the number of bits it can transfer in a second. Modems rated in kilobits per second are now the standard.

Kermit This is a protocol for transferring files during direct dial-up communications that's named after a Muppet (seriously). Kermit is sound but old and can be very slow--slower than Xmodem, Ymodem, and much slower than Zmodem.

kernel  Modern operating systems are typically built in layers, with each layer adding new capabilities, such as disk access techniques or a graphical user interface. But the essential layer, the foundation on which the rest of the operating system rests, is typically called a kernel.

kilobyte  Although kilo is Greek for a thousand, a kilobyte actually contains 1,024 bytes (that's 2 to the 10th power). In other words, a thousand bytes is actually less than a kilobyte.

L

L1 cache
level one cache  Another term for primary cache.

L2TP
Layer Two Tunneling Protocol  L2TP is a secure protocol used for connecting VPNs (Virtual Private Networks) over public lines such as the Internet. It is essentially a combination of two other secure communications protocols: PPTP and Cisco Systems' L2F.

LAN
local area network  A local area network is a short-distance network used to link a group of computers together within a building. 10BaseT Ethernet is the most commonly used form of LAN. A piece of hardware called a hub serves as the common wiring point, enabling data to be sent from one machine to another over the network. LANs are typically limited to distances of less than 500 meters and provide low-cost, high-bandwidth networking capabilities within a small geographical area.

laser printer  While considerably more complex and expensive than most other common printer types, laser printers are capable of producing extremely high-quality text and graphics (including color) at fantastic speeds

latency  In networking, latency and bandwidth are the two factors that determine the speed of your connection. Latency is the time it takes for a data packet to move across a network connection.

LBA
logical block addressing  Until LBA, PCs with IDE controllers were limited to accessing hard disks of 528MB or less. Why? Because IDE's addressing model didn't allow addresses large enough to work with bigger drives. (It wasn't really IDE's fault.

LCD
liquid-crystal display Created by sandwiching an electrically reactive substance between two electrodes, LCDs can be darkened or lightened by applying and removing current. Large numbers of LCDs grouped closely together can act as pixels in a flat-panel display.

LDAP
Lightweight Directory Access Protocol Directories containing information such as names, phone numbers, and addresses are often stored on a variety of incompatible systems. LDAP provides a simple protocol that allows you to access and search these disparate directories over the Internet.

leased line A dedicated private line that is used primarily to link two remote local area networks (LANs) together. Unlike frame relay, this line transmits data at only one speed depending on the purchased bandwidth. Customers pay a flat monthly rate for this service.

LED
light-emitting diode  In electronics terms, a diode is a semiconductor device through which current can go in only one direction. As a side effect, light-emitting diodes produce either visible or infrared light.

Lernout & Hauspie  Lernout &Hauspie Speech Products work in speech recognition, text-to-speech, and encoding speech and music into digital formats. Their audio encoding uses three separate techniques (sub-band coding, codebook excited linear predictive coding, and harmonic coding) for a range of compression rates and sound qualities.

linearity  Linearity refers to a monitor's ability to display shapes such as squares or circles in various places without any stretching or distortion. Poor linearity causes onscreen objects to look flattened or squished. Related screen geometry problems include trapezoid error and pincushioning.

line provisioning Line provisioning is the way telephone companies set up ISDN to work with their customers' equipment. Since equipment and central office switching features vary, customers must specify how the ISDN line should be provisioned when they order it. If you're lucky, your hardware manufacturers will have assigned codes to make ISDN configuration easier. This clumsy setup procedure is necessary because ISDN is used for many different purposes and is not yet fully standardized.

Linux  What do you do if you're not happy with any of the current operating systems? You build your own, of course. That's exactly what Linus Torvalds did. His freely distributed, Intel-processor-based alternative to Unix, Linux (pronounced lih-nucks), is currently used by hundreds of thousands--and possibly millions--of people around the world. While Linux began life primarily as a hobby for supergeeks, the operating system has made some inroads into corporate life, particularly as an inexpensive substitute for high-priced Unix Web servers. Linux is available from a number of vendors for several hardware platforms, including Intel x86, DEC Alpha, Sun Sparc, and Motorola PowerPC.

LOL
laughing out loud  This shorthand term is used in postings and online chat to show appreciation of a witticism in a previous posting.

lossy  Graphics files are big, and most file formats (such as BMP, TIFF, PICT, and PCX) are inefficiently coded, so they are larger than they need to be. So how do graphics programmers save disk space? They develop compression techniques. Graphics compression techniques fall into two camps: lossless and lossy. Lossless techniques throw away redundant bits of information without affecting the quality of the image.

LZW compression
Lempel Ziv Welch compression  This data compression technique is an adaptation of two techniques by Abraham Lempel and Jacob Ziv.

Glossary 2 (M -Z)