3G

Short for Third Generation and typically used when describing new, data capable cell phones and the networks required to service them. Both cellular phone makers and wireless carriers have determined that data services are the wave of the future, so they've built phones with reasonable screens and processing capability and networks that can deliver data at rates of greater than 128 kilobits per second (kbps). Older cell phones were often limited to very slow (think 9.6 kbps or 14.4 kbps) data transfer rates, but newer phones and services typically can be measure in the hundreds of kbps. 

The "generation" part of the name relates to how fast the data services provided to the cell phones, smart phones and PDA-enable devices. Unfortunately, the US is well behind other regions of the world--most notably Japan, Korea and Western Europe--when it comes to deploying 3G networks and, without those networks--the 3G phones have nothing to take advantage of. When 3G networks and phones do finally arrive here, expect wireless notebook-like experiences. But don't hold your breath, because it's probably still a few years off.

64-bit

A reference to the number of individual data bits that a computer and software running on it can process in a single byte, er bite. 64-bit computing refers to microprocessors, operating system software and applications that are designed to use 64 bits of data at once. In order to have true 64-bit computing, all elements of the hardware and software system need to be able to work "natively" in 64-bit.

The amount of independent memory that a chip can access is also determined by its "bit level". Current 32-bit processors, such as the Pentium 4, are limited to working with 4 GB of RAM, whereas 64-bit processors can (theoretically at least) work with over 1 terabyte (TB) of RAM.

Aspect Ratio

The dimensions of TV screen or monitor, when expressed in mathematical relation to each other, are referred to as a display's aspect ratio. A simpler way to think of it is simply the "shape" of the screen. Traditional TVs and monitors have a 4:3 (called 4 by 3) aspect ratio, meaning that the width of the screen when compared to the height can be expressed as a ratio of four to three. This is a fairly square shape. 

Newer widescreen TVs and computer displays, on the other hand, have a proportionally longer width, resulting in a more rectangular shape. These widescreen displays typically have a 16:9 aspect ratio, although it's not uncommon to also see 15:9 and 16:10.  (These differences have to do with the specific pixel resolution of the displays. A resolution of 1,280 x 720, for example, works out to 16:9, but 1,280 x 768 is 15:9.)

HDTV requires a widescreen display and many computer users find that the wider format screens are an attractive option since they provide a visual experience more akin to what are eyes are designed to see. As a result, wide format screens are becoming increasingly common in more and more devices.

ATSC Tuner

An acronym for Advanced Television Standards Committee Tuner, otherwise known as an HDTV tuner. The ATSC was the group that defined the standard for over-the-air HDTV reception and ATSC Tuners are television tuners designed specifically to receive and display digital, high-definition TV programming. (The similar sounding NTSC, which stands for National Television Standards Committee, is the long-time standard for regular, standard definition television.)

Some televisions are starting to include ATSC tuners built-in, but most still do not. Instead, many people are buying ATSC tuners in the form of standalone digital set-top boxes. Some boxes include only an ATSC tuner, while others include an ATSC tuner along with either an HDTV satellite receiver or an HDTV cable box. Regardless, all ATSC require a connection to an antenna (since they only work with over-the-air broadcast transmissions) in order to work.

Beta

The second letter in the greek alphabet, commonly used to refer to a pre-release version of a software program. When programs are first created by software developers, they go through several stages before they are released as commercial products. The first version of a program is called an "alpha". While there are no hard and fast rules, alpha versions typically contain the basic structure and menu options that exist in a final program, but not everything works and many functions still have "bugs" or problems with them. Alpha versions are almost never released to the public.

Once a program has been completed, it moves to the beta stage. Again, while there are many differences among companies, most beta versions are "feature complete," meaning they have all the functions that are supposed to be in the program and they generally work as advertised. However, beta versions haven't been through rigorous testing and so they often have bugs in them as well. Many companies offer beta versions to the public with the caveat that they might (and probably do) still have issues, so you need to use them at their own risk.

BIOS

An acronym for Basic Input/Output System, the basic software that sits at the heart of PC hardware. The BIOS is stored in a tiny, reprogrammable chip that sits on a computer's main circuit board--often called the motherboard. When a computer is first turned on, the BIOS immediately starts and sets up any attached hardware, such as hard drives and optical drives. At the end of its boot process it begins the process of loading any operating system stored on the primary hard drive. In other words, the BIOS loads before Windows.

You can change the settings in your BIOS by entering the BIOS (or CMOS) Setup when your computer first boots--typically by hitting a key such as F2 or Del. In some cases, you need to hit the Esc key first. Changing the BIOS settings can be helpful if you're having problems with your hard drives or optical drives or if there is a problem booting your PC.

Blog

A shortened version of "web log," a kind of online diary that individuals publish for others to read. Blogs are a very fast, efficient way for people to share information/commentary in an online form. Everyone from company CEOs to kids are now creating blogs. Many blogs conform to the RSS (Really Simple Syndication) standard, which allows you to "subscribe" to them and have the latest information sent to you automatically, typically via e-mail

Blogs often consist of a series of data entries that might include a few paragraphs (or few pages) of text and photos or other content. You typically view blogs through your browser, much as you would a regular web page, but you can also view them via dedicated RSS "reader" programs.

Blue Laser

A laser that generates light in the blue frequency, which is higher than traditional red lasers (such as the kind found in CD-ROMs and DVDs). This higher frequency allows blue lasers to read and write data in much smaller spaces which, in turn, enables them to store more data in a given space. The direct result is that blue laser optical discs, such as Blu-Ray and HD DVD, permit higher capacities to be stored in a regular 5 1/4" optical disc. For example, Blu-Ray discs offer up to 25 GB/layer or 50 GB/side, a 10x increase over traditional DVDs.

Bluetooth

A low-power wireless data standard named after a famous Norse/Danish king who was known as a great compromiser. Bluetooth was originally designed by a consortium of mobile phone companies and was intended to develop a standard for universal wireless headsets for cell phones. Other companies got involved in the standard however and its scope was broadened to cover any peripheral device that would be used within a ten meter (30-foot) range of a host device. As a result, Bluetooth is now being used with wireless keyboards and mice and for wireless synchronization between PDAs, cell phones and PCs.

Bluetooth, which features a data rate of about 1 Mbps (or only 1/10th of that of 802.11B) and uses the same 2.4 GHz frequency band as WiFi, was originally expected to have a major impact on mobile devices, but its slow rate of adoption and the rapid rise of WiFi has relegated Bluetooth to a more minor role. Nevertheless, it is has proven to be a good complementary wireless technology and is ideal for low power devices and peripherals.

Browser

A program for your PC or Macintosh that allows you to view pages of information on the world wide web or internet. Technically, a browser is an HTML rendering application, meaning that it can read and interpret files created in the HyperText Markup Lanaguage (HTML) format and display them on your computer's screen. The most popular browser is Microsoft's Internet Explorer, but other popular options include Mozilla Firefox, Opera Software's Opera and Apple's Safari. 

Not all web browsers can read all web pages and other web ad-ons. In that case, the browser look for help from "helper" applications, such as Macromedia's flash player, Apple's QuickTime, etc.

CableCard

A cable industry standard found on new digital TVs that enables the reception of digital cable signals via a credit card-sized receiver. Essentially, CableCard replaces a set-top box with a receiver that plugs into a slot in the back of a TV. As convenient as this is, however, current incarnations of CableCards are one-way only--meaning they can receive and descramble digital TV signals, but they cannot send data back to the cable company. This prevents them from offering video-on-demand and other two-way services that standalone set-top boxes continue to enable. 

CCD

Acronym for Charge-Coupled Device, the imaging sensor found in many digital cameras. A CCD is a special kind of circuit/semiconductor chip that converts light energy into electrical energy. This, in turn, is converted into a series of ones and zeros--the digital bits that make up every digital image. CCDs also map the content of the image they receive to a color spectrum--this enables them to have excellent color accuracy. 

In discussing the most popular specifications for digital cameras--the number of megapixels--what you're actually talking about is the resolution of the CCD found inside the camera. 

Chipset

A set of two chips (typically) that sit on a computer's motherboard or main circuit board and work in conjunction with the main processor. The chipset is a critical part of an overall computer system and determines support for important features such as the type of connectors a PC includes, the speed and type of memory that can be used, and, in some cases, the graphics capabilities of the system.

Codec

A shortened version of the phrase compressor/decompressor, a piece of software that takes media files (such as video and audio) and reduces them in size for recording and/or transmission over a network connection and then decompresses them for playback. Without compression, high-quality video files would be very difficult to record and even more difficult to transfer from one place to another because of the enormous size and bandwidth requirements that they have.

Some of the more well-known codecs include MPEG-2, MPEG-4, Windows Media Audio (WMA) and Windows Media Video (WMV).

Cookies

A tiny text filed used by many web sites to help keep track of where you have been on the site and any preferences you may have selected. Unless you specifically request to see them, cookie files are typically transferred from the server hosting the web site directly to your PC's hard drive without your knowledge. (On Windows-based PCs, they're stored in the Cookies folder, which is located inside the Documents and Settings folder off the main root--typically C:--of your hard drive.) While this sounds somewhat nefarious--and in a few cases can be--the vast majority of cookies are innocuous and many can actually be useful. For example, cookies can do such things as remember your username and password or any other settings you may have made, which makes it easier for you the next time you visit that web site. The site checks to see if you have a cookie file that it had previously sent, and if it finds one, it uses the settings stored in the file. If it doesn't find one, you simply have to make the settings again.

Database

A collection of information stored as a series of individual records--also the name for software programs that allow you to create and manipulate these records. At the simplest level, databases can be thought of as high-tech versions of a collection of 3 x 5 index cards. At a more sophisticated level, databases can also do things like track information results from a scientific experiment generating megabytes of data every second. 

Each record in a database typically consists of numerous individual fields, each of which stores the basic data. Database fields can be as simple as first name or last name in text form, but can also hold images, video, music and any other kind of digital file. The true value of a database comes from the manner in which you can interact with the data--whether that be simple searching, charting of results, or finding patterns.

Distributed Audio/Video

A type of system that enables you to play audio or video content that is stored or located on one device across other devices. In other words, a type of audio/video networking system. Many distributed audio/video systems feature a media server that holds the content and then "adapters" that you attach to regular TVs and/or stereos that serve as the playback systems for the content. In some cases, these media servers are specialized, dedicated devices, but in others, general purpose PCs with specialized software are used.

The beauty of a distributed A/V system is that it allows you to have access to any audio or video content that you own from anywhere in your home (at least, anywhere you have a TV or stereo).  More sophisticated systems can find content stored or located (such as in a large CD or DVD changer) across multiple devices and present you with a single library of choices.

DivX

A type of compressed media file format used to store and send movies and other video content in digital form. DivX, which is currently in version 6.0, can compress MPEG2 files (which are themselves compressed) by a ratio of about 10:1 and digital home video DV files up to 25:1. In order to playback DivX files, you need either a software player in order to  play them back on your computer, or a standalone DVD player that supports DivX (not all do). To create DivX files you need a program called an encoder (or an application that offers encoding as one of many features) that specifically supports the creation of DivX files--not all video editing programs do.

Several years, Circuit City (and a few other vendors) made a failed attempt at another technology called DivX that was essentially a type of DVD rental scheme. The current DivX format has nothing whatsoever to do with that former type of DivX.

Driver

A small piece of software that communicates between an operating system and some piece of hardware on a PC--either a peripheral, such as a printer, or a component of the PC, such as a graphics card. Sometimes also referred to as device drivers, these bits of software are some of the most important parts of your system--but also some of the most troublesome. Driver conflicts --where two drivers essentially interfere with each other--used to be some of the most common (and most frustrating) problems you would run into with PCs. Thankfully, things have improved tremendously over the last few years.

When you install software that comes with a new piece of hardware, you are installing the driver (as well as other applications/utilities in many cases). With later operating systems, such as Windows XP and MacOS X, a large database of drivers is built-in, which means you may not have to physically add any new software at all. However, your computer will use the new software driver to communicate properly with the device. 

DRM

An acronym for Digital Rights Management, which is a system for ensuring that copyrighted material, such as music and movies, cannot be freely copied. There are many different types of DRM systems but, unfortunately, they don't all work together. For example, one of the most notable DRM's is Apple's FairPlay, which is used within iTunes, but it can't interact with the Microsoft DRM system used in Windows Media Player. The practical result is you can play music from iTunes or music you bought at the iTunes Music Store within Windows Media Player.

DRM systems are software-based and typically include some form of encryption software to ensure that hackers can't easily get access to the copyrighted material.

DSL

Acronym for Digital Subscriber Line, a type of connection to the Internet that is carried over regular phone lines, but differs fundamentally from regular modem connections. DSL technology provides a fast (often called "broadband") connection to the Internet, typically at rates of at least 384 Kilobits per second (Kbps) or higher. DSL technology essentially splits a phone line into two components--specifically, frequency bands--and allows both voice and data connections to occur in each of those components simultaneously. This allows you to both speak on the phone and use an Internet connection with a PC or other device at the same time.

DSL service requires a phone company to enable it at their office and the installation of a DSL modem near your PC. The DSL modem serves as a "translator" that converts data packets from PC form into a form that the phone lines can carry and back again.

Common variations of DSL are called ADSL (Asymmetric Digital Subscriber Line), in which upload speeds are slower (really, different or asymmetric) from download speeds, and SDSL (Symmetric Digital Subscriber Line), in which upload and download speeds are the same.

Dual Core

A new type of microprocessor that has the equivalent of two chips in one. Dual core processors have two central processing units packaged into one physical chip. Microprocessor companies such as Intel and AMD are moving to multicore because it's the only way they can keep up with the performance demands of Moore's Law, now that physical barriers (such as heat and power requirements) are preventing significant speed improvements in single core chips.

As appealing as dual core  may sound, however, new dual core processors do not give you 2x the performance of today's existing single core processors. Part of the issue has to do with how the chips are designed and how they function in a system with a single set of memory, hard drive, etc. that needs to be shared across both processors. However, the primary problem is a software one. To really take advantage of dual core processors, you need the operating system, applications and drivers that can really take advantage of two (or more) cores.

DVI

 Digital Visual Interface--An interface standard designed to send video data in digital form to a computer monitor or digital television. DVI provides the best possible visual quality when used with flat-panel LCD monitors or televisions that include digital display devices, such as plasma panels, LCD panels, DLP (Digital Light Processing) chips and others.

In order to use DVI, you need source devices (such as your PC in the case of a monitor, or set-top box and DVD player in the case of a television) that include DVI outputs and, at present, not many do.  If you do, however, a pure digital connection offers a tremendous boost in quality.

DVD±RW/DVD±R

DVD-Rewritable (in the + and - formats) and DVD-Recordable (in the + and - formats). Rewritable discs can be written to over and over and information can be erased, while recordable discs can generally be recorded once and information cannot be erased. The + and - refer to two incompatible recordable DVD formats that differ in how they read and write data to the disc. Bottom line, you can't use discs created for one in the other. Recently, some drives are starting to support both formats. 

The recordable disc formats are used both in computer applications as well as standalone consumer electronics devices.

DVR/PVR

Acronym for Digital Video Recorder, sometimes also referred to as a Personal Video Recorder. DVRs, such as the Tivo device, are video components that record TV programs in a manner similar to VCRs, but onto large hard disks instead of tape. Not only does this digital recording method provide better quality signals, it also enables you to search through the recorded results in any number of ways. For example, you could find everything you've recorded with a particular actor or created in a particular year and what have you. In addition, because all this extra information is part of the onscreen guide that all DVRs provide, you can also decide what to record in the first place based on these kinds of criteria.

DVRs also have the ability to pause live programs (in addition to any recorded programs) because the hard drive can continue recording if you hit the pause button. When you continue watching, the device simply reads the digital file on the hard drive from where you had stopped while continuing to record the rest of the program.

To date, most DVRs have been standalone devices, but Windows Media Center PCs offer similar capabilities inside of a PC. Over time, you can expect to see DVR-like functionality incorporated into more set-top cable and satellite boxes, as well as built directly into TVs and other home entertainment products.

EDGE

One of the several high-speed data networks available now for cell phones, EDGE  stands for Enhanced Data GSM Environment, a faster version of the GSM (Global System for Mobile) standard. EDGE offers up to 384 Kbits/sec, which allows the transfer of large images, movie files, mapping services and other types of multimedia data that would not be possible with the previous data standards.

An  EDGE network, like other 3G (third generation) cell phone standards, is put into place by the cell phone service providers. In the case of EDGE, it uses the TDMA (Time Division Multiplexing Access) method of transmission--versus the competing CDMA (Code Division Multiplexing Access) standard. A newer standard called UMTS (Universal Mobile Telecommunications Service) will eventually replace EDGE once the networks have been completed.

EVDO

An acronym for Evolution Data Only, a type of wide area wireless network for data that builds on the CDMA cellular telephone standard. EVDO improves upon (hence is an "evolution" of) existing data networks based on CDMA called 1XRTT. Both types of networks give you the ability to have high-speed wireless connections (via a plug-in car for your notebook PC) anywhere within a metropolitan area that offers the service. In other words, you don't need to be near a WiFi Hotspot.

The big improvement with EVDO is that while 1XRTT data networks could give typically data rates of about 70-80 Kbps, EVDO rates are around 400-800 Kbps, about the same as DSL or Cable.

Firewire/IEEE 1394

A high-speed (400 Megabits per Second (Mbps) or 800 Mbps) connection interface found on many new computers, peripherals and consumer electronics devices such as digital camcorders. Firewire/;1394, which--like the USB interface--includes support for plugging in devices while they are turned on, is ideally suited for A/V applications because it includes support for synchronized audio and video transfer.

Note that not all Firewire/1394 connections are created equal and not all can connect to one another.

GSM

An acronym for Global System for Mobile communication, GSM is one of the most popular digital cellular phone network standards in the world (and particularly in Europe). As a digital network, GSM networks fully supports high-speed data transmissions as well as voice. The way that GSM works is that it digitizes and compresses the audio data from your phone, then mixes it together (multiplexes to be precise) the signals from up to two other calls and then sends the signal along the cellular network.

GSM competes with WCDMA (Widespread Code-Division Multiple Access) and TDMA (Time Division Multiple Access) and all three are often referred to generically as 3G phones, meaning they're both digital voice and high-speed data capable. One benefit of GSM phones is that they can often be used in foreign countries while travelling, whereas other technology cell phones typically do not.

HDMI

Acronym for High Definition Multimedia Interface, a new digital interconnection standard that carries both a DVI (Digital Visual Interface)-compatible digital video signal and multichannel audio over a single cable. Displays and devices incorporating DVI have just started to become available in the marketplace.

HDMI is completely backwards compatible with DVI with HDCP and can carry mulitichannel DVD Audio and SuperAudio CD (SACD), or regular Dolby Digital, all on one cable. 

HDTV

Short for High Definition Television, a broadcast and display standard for the transmission and reception of television programs that have approximately six times the resolution of current "standard definition" programs.  While there are technically as many as 18 different HDTV standards in the US (there are different standards in different countries), the two primary ones are referred to as 720p, or 720 progressive (1,280 x 720 in monitor resolution terms) and 1,080i, or 1,080 interlaced (1,920 x 1,080). Different programs can be broadcast in different resolutions, although most major networks stick with one particular resolution. For example, ABC uses 720p, while CBS uses 1080i.

High definition viewing requires that programs be filmed and created in HD, then broadcast in HD, then received with an HD tuner and finally displayed on a set that supports high definition resolutions. The tuners for high definition are sometimes referred to as the ATSC (Advanced Television Standards Committee) tuners.

HSDPA

An acronym for High-Speed Downlink Packet Access, the latest network connection being touted for data-capable cell phones. Sometimes referred to as 3.5 G, this new telephony standard offers the promise of data download speeds of 8-10 Mbits per second--in other words, as fast as older wired Ethernet and 802.11b Wi-Fi.

Initial deployments are expected to begin in earnest in 2006.

Hypervisor

An operating system for operating systems, a hypervisor is a low-level piece of software that can be used to load any one of several operating systems in computers  that support virtualization. Newer processors have the ability to act as if they were two (or more) independent computers but in order to take advantage of this capability, you need software that can serve as a buffer layer between the CPU (central processing unit) and the operating systems.

Software such as Virtual PC, which lets you run Windows on Mac OS X, is a simple example of a hypervisor.

IPTV

An acronym for Internet Protocol Television, a means of sending TV-like video programs over the Internet. Many phone companies are looking to compete with cable and satellite companies for delivering TV service to people's homes and, in their case, they plan to leverage the Internet infrastructure to do so. IPTV systems don't use the wide-open Internet to deliver content, but use Internet protocols and more of a "walled garden" approach. They will still require a set-top box to plug into your TV (for now), but will bring the programs to that box via Internet-style connections.

In addition to IPTV, there are several smaller companies hoping to leverage the Internet as new broadcasting medium for bringing TV-style content straight to PCs and, eventually, TVs.

LCD

An acronym for Liquid Crystal Display, a type of screen technology that enables the creation of flat, thin displays. Large  LCDs, which are used in notebook PCs, desktop monitors and TVs, consist of a sandwich of materials including multiple layers of glass, a series of filters that turn white light into separate red, green and blue colors, and a layer of liquid crystals. Behind the screen is a light source, called a backlight, that shines white light through the different layers. The liquid crystal portion consists of material that when it receives an electrical charge, twists in a manner that allows either more or less light to pass through.

LCDs were first created in the 1970s and can now be found on virtually any electronic device or home appliance being sold.

LCOS

An acronym for Liquid Crystal on Silicon, a type of projection display technology that uses a tiny (less than 1") chip to reflect light onto a screen. As with both DLP (Digital Light Projection) and LCD projection TVs, a lamp creates light that either bounces off of or passes through the tiny display chip and that image is projected onto the back of a screen inside the TV. In the case of front projectors, the image is projected onto a wall. LCOS differs from LCD rear projection in that the display device is actually a tiny silicon chip, as opposed to a miniature LCD panel. One of the primary benefits of the LCOS approach is that the images can switch very quickly, leading to a smoother picture without motion blur.

TV vendors often use their own names for their own variations on LCOS. Sony, for example, calls their LCOS technology SXRD, while JVC calls theirs DILA.

Linux

An operating system for personal computers and other devices that was originally created by a gentleman named Linus Torvalds and built around the core principles of the Unix operating system--hence the name Linux. Some PC enthusiasts consider Linux a superior alternative to Microsoft Windows for desktop PCs because of its stability (as well as the fact that it's free) and a growing base of applications and drivers is now available for the upstart OS.

Part of Linux' fame is due to the fact that it is the most well-known example of open source software, a category of products where the original source code used to create it is made freely available. With most commercial applications, the source code is kept private, much like a secret recipe. In the case of open source, such as Linux, however, anyone can have free access to the code and make changes and improvements to it. The one catch is that any of those changes and improvements have to be made available to the general community at no charge. As a result, there is a large community of developers who donate their time to continuing developing and improving Linux.

Megapixel

A term used to describe the resolution of digital cameras and, in some cases, displays. A megapixel technically means 1 million pixels, or picture elements, go into the creation of an image. The higher the number of megapixels, the more detail that can be captured (or displayed). For example, an 8 megapixel digital camera can use up to eight million tiny elements to create an image--think of it as 8 million tiny dots of color that are formed together to create an image.

For digital cameras, typically 4 megapixels and higher will provide sufficient resolution to print an 8" x 10" photo without seeing any blurriness.

Microprocessor

The primary chip used in personal computers, the microprocessor--sometimes also called the central processing unit or CPU-- is the brains of any personal computer. The processor is the component that runs the software on the PC and controls the other pieces inside a computer. Common examples of processors are Intel's Pentium line of CPUs.

In fact, the most common kind of processor family are those based on what's called the x86 architecture. The architecture of a chip refers to how it is internally structured, how it works and how software must be written in order to work on it. The x86 name comes from Intel's original line of 16-bit processors starting with the 8086, which is found in the first IBM personal computer.

MIDI

Musical Instrument Digital Interface, or MIDI, is a "language" used to transmit musical performance information (and more) from one electronic instrument to another and/or between electronic instruments and computers. Most commonly, MIDI is used to record the "keystrokes" of someone playing an electronic keyboard or other MIDI controller (in other words, anything that can generate a MIDI message) on a PC. MIDI does not record audio, but simply the notes that were played, how long they were played, how loud there were played, etc. 

Devices or software programs that record MIDI data are called sequencers and they are extremely powerful and flexible tools for music creation. MIDI information is stored in MIDI files and these files can be played back by most standard software media players as well as MIDI hardware devices such as synthesizers, drum machines and more. MIDI files do not contain traditional music notation information, but they can be imported by notation programs and turned into printable music. 

MIMO

An acronym for multiple input/multiple output products, specifically those wireless networking products that feature multiple radios for broadcasting and receiving data. In the ongoing quest to improve the performance and reliability of 802.11-based wireless products, several companies have determined that by equipping wireless cards and routers with multiple transmitting and receiving devices, they can reach higher speed levels and do so over slightly longer distances. Unfortunately, there are several different ways to implement the multiple input/multiple output (MIMO) concept and because there is no standard way of doing so, several vendors have begun to release incompatible products. Some of these are referred to as "pre-N" routers, in recognition of the 802.11n standard--which is still a work in progress and expected to be one through 2005 and into 2006.

Once the standard is ratified, MIMO and "pre-N" products will be a thing of the past, but until then, be prepared for a lot of confusion among the already complex world of 802.11 wireless networking.

MP3

Short for MPEG 1, Audio Layer 3, a digital audio file format that was first created as part of the first version of the MPEG (Motion Picture Exports Group) video standard. Though not originally designed to stand on their own, MP3 files quickly became recognized as an efficient way to store and transfer music digitally, particularly after the rapid rise of the Napster online music service (which used MP3s as its default file format). MP3s compress audio files off CDs to approximately 1/10 of their size while retaining reasonably good audio quality. Note that not all MP3 files sound the same--there are varying resolutions, expressed in Kilobits per second (Kbps)-- supported within the format. The higher the compression, the lower the bit rate, the smaller the file and the lower quality the sound. Less compressed files, on the other hand, have higher bit rates and sound better, but are also much larger. Compression rates typically range from 32Kbps to 320Kbps.

Multitrack Recorder

A device that records audio (typically music) onto independent tracks, or locations, and then lets you combine them into a complete whole. Modern musical recordings are made by musicians playing musical parts, often one or two at a time, and recording those parts while listening to previously recorded parts (or tracks). The ability to listen while recording new material is known as overdubbing.

Multitrack recorders used to use tape, but most now use hard drives--either in dedicated devices or using a PC or Mac's hard drive and special recording software.

Partition

A logical section of a hard drive. While most computers and other devices that use hard disks only have one physical disk it is possible to split them into several sections and treat each one as a separate entity. The process of creating these sections or logical dividers is called partitioning the disk. In the old days of PCs, this process was often done with a DOS-based program called fDisk, but a variety of Windows-based (or Mac OS-based) utilities are now used for this task.

Different partitions can be used to simply divide programs from data or to even store different operating systems on the same computer. Only one partition is allowed to be the active or main partition at any one time, but it is often possible to see multiple partitions at once. In Windows Explorer or the Mac's Finder, each partition appears to be a separate hard drive. 

PC Card

A format for credit card-sized peripherals and expansion cards that plug into notebook computers and other small electronic devices. The term is also used to describe the slots into which these devices are plugged. PC Cards can be used to add a wide variety of things including memory, input/output devices such as modems, USB 2.0 ports, and hard drives. PC cards come in three basic sizes or types, the primary difference being the width of the cards. Type 1 cards are 3.3 mm thick and are typically used for memory; Type II cards, the most popular by far, are 5 mm thick and used for a wide variety of purposes; and Type III cards are 10.5 mm thick and often used for miniature hard drives. Type I and II cards can fit into any standard PC Card slot, and Type III cards essentially fill the space of two PC card slots (which is why some notebooks come with two stacked PC card slots). Early versions of PC Cards and PC Card slots were often called PCMCIA (Personal Computer Memory Card International Association), after the association that developed the standard.

A new format for PC Cards called, appropriately, NewCard, will start to appear on devices later this year. NewCard offers smaller sizes that can fit two cards side-by-side and a faster interface standard that will enable things like the ability to add a new graphics card to a notebook PC via the NewCard slot. 

PCI Express

A newer, faster version of the PCI (Peripheral Component Interface) bus found inside PCs. PCI Express, as with PCI, is used to connect between internal peripherals, such as video cards, and the rest of the system (particularly the CPU). PCI Express uses a different physical connector than PCI in addition to running at a faster rate, so old PCI cards won't fit into PCI Express slots inside a PC.

In addition to running faster on its own, PCI Express has the option for "lanes" of multiple data streams (signified as X4, x8, x16, etc.). New graphics cards can take advantage of the x16 capability, for example, and have more than twice as much bandwidth as AGP 8X. (Speaking of which, PCI Express will replace the AGP bus as well as PCI.)

PDA

An acronym for Personal Digital Assistant, a name that was first associated with Apple's Newton device but is now more commonly associated with electronic organizers like Palm devices and Pocket PCs. PDAs typically include calendar and contact information along with other simple applications that you can use to store and share photos, videos and almost any kind of data/information that you like. Virtually all PDAs come with software that you can use to synchronize the data on the device with your PC or Mac.

While standalone PDAs are still popular devices, we've begun to see PDA-like features be incorporated into other devices, such as advanced cellular phones. 

Phishing and Pharming

Two types of Internet-based hacking techniques in which rogue web sites are created in order to try and trick people out of unknowingly sharing information such as bank account numbers and passwords. In the case of phishing, which is a play on "fishing," people are tempted with a "lure", such as a bogus e-mail from a bank or credit card company that says they need to verify certain information. If you click on the link, you're taken to a site that may be a very good copy of the actual site and typically asked to log in. You can usually tell the site isn't real, however, by the website address (URL).

In the case of pharming, a lure isn't used--instead real web sites are being redirected to bogus copies through a phony DNS (Domain Name Server). Once again, careful checking of the actual address that's shown on your web browser's address line can help you avoid this type of cybercrime and help you avoid potential identity theft.

Plasma

In the context of technology, plasma refers to a type of flat-panel display technology that uses gas plasma to generate the image. Plasma TVs and plasma displays used for other applications, such as moving signs in retail stores and movie theaters, all feature two thin sheets of glass and a special gas mixture that carries electrons to the phosphorescent material painted on the inside of the front glass. The end result is an image that has the color richness, immediate responsiveness and wide viewing angle of CRT displays, but in a much thinner size, similar to that of LCDs (liquid crystal displays).

While a few companies offers plasmas at sizes under 40", most plasmas displays are 42" and larger, making them well suited to their roles as home theater or commercial displays. 

PMP

An acronym for Portable Media Player, a type of handheld device that can play back media files, including audio, still images and video. PMPs, which typically feature 3-4" color screens and built-in hard drives, are somewhat akin to MP3 players on steroids. Not only can these devices function as MP3 audio players, they can also playback video files that you transfer over to them from your PC or, in some cases, directly from a TV set-top box, such as a Tivo or other DVR (digital video recorder).

Podcast

A type of broadcasting that uses the Internet to transfer audio files to people who "subscribe" to the content. Professional media outlets, as well as ordinary individuals, can create their own content--typically audio programs that are similar to (or exact copies of) radio programs--and deliver them to listeners automatically. Podcasts are web feed that commonly use RSS (Really Simple Syndication--see glossary entry) as the means of delivering the content. You can either download podcasts manually, or with certain applications, you can "subscribe" to podcasts and have them delivered to you automatically whenever a new program is uploaded online.

While the term Podcast implies a connection to the ubiquitous Apple iPod, you don't need an iPod to listen to a Podcast (although an iPod and iTunes does make it easy to find and transfer Podcasts to your device).

Progressive Scan

A characteristic of certain video signals and devices that create or display them in which the video image is generated in one continuous (i.e., "progressive") motion. Video images that come from DVD players, for example, or that are shown on TVs are made up of a series of lines. With older TVs and most newer CRT (or picture tube)-based TVs, a single frame of video is actually broken up into two sub-segments referred to as fields. The first field consists of the odd lines of the image (1, 3, 5, etc.), while the second field fills in the even lines (2, 4, 6, etc.). On newer digital TVs that are progressive-scan capable, when they receive an image sent from a source device (such as a cable or satellite box) that's in the appropriate format, they can start from line 1 and move continuously through all the scan lines until the entire frame is complete.

While this may seem obvious--and it has always been the case with computer monitors--progressive scan is a relatively new but now widely accepted part of modern consumer electronics (CE) devices.

RAID

An acronym for Redundant Array of Inexpensive Disks, a method for using multiple hard disks as a single unit. There are several different types or levels of RAID systems, some of which require at least three or more hard drives. However, the most common types of RAID systems, Level 0 and Level 1, only require two drives. RAID Level 0, commonly called striping, treats two drives as one large single drive and spreads your files across the two drives. RAID Level 1, commonly called mirroring, makes exact duplicates of all your files on each drive. An advanced version of RAID, called Level 5, combines the benefits of striping and mirroring along with fault tolerance, which ensures the integrity of your data, but it requires more than two drives. New variations on RAID levels 0 and 1, sometimes referred to as 01 or 10, give much of the same benefits (minus some of the more sophisticated fault tolerance techniques) but with only two drives.

All RAID systems require special RAID controller hardware, either in the form of a dedicated controller card or built into a system's motherboard. Many newer computers include RAID support and have software tools that let you enable it once you physically install a second drive into the system.

RAM

A TLA (three-letter acronym) for Random Access Memory, the main working area that a computer or other electronic devices uses to load software and files into and perform its calculations. Most memory comes in the form of DRAM, or Dynamic RAM, which is a type of memory whose contents are refreshed on a regular basis.  Another important type of RAM is called Flash Memory, or just Flash for short. Unlike DRAM, which requires power in order to hold data and loses its content when power is removed, Flash memory can hold and store content without power. In a way, this makes Flash memory work like a tiny hard drive, except that flash memory is much smaller and has no moving parts.

Registry

The component of the Windows operating system (in virtually all flavors, including Win 95 onward) that stores critical system settings and preferences. Technically, the Registry is a large database made up of the System.dat and User.dat files that stores settings for Windows as well as virtually all the software you install on a computer--from application programs to drivers for hardware devices. The Registry is organized into six main keys, called "Hkeys," which are further subdivided into hundreds of categories and thousands of individual keys. 

Normally you don't need to (nor do you want to) mess with the Registry and, thankfully, most applications and drivers take care of their interactions with the Registry behind closed doors, as it were. However, occasionally in the course of troubleshooting, you'll find yourself needing to edit a setting or two in the Registry. Typically, that's done through the RegEdit application, which is bundled with Windows. One other interesting note is that all the Control Panels in Windows are actually miniature registry editors as they directly change system preference settings stored in various parts of the Registry.

Resolution

The number of individual picture elements (pixels) or image dots that make up an image is called its resolution. The higher the resolution, the more individual picture elements or image dots there are in a given area (and hence, the smaller each individual pixel is).

For printers and scanners, resolution is measured in dots per inch (dpi), while for digital cameras, resolution is measure in megapixels (millions of pixels). For displays, including monitors, notebook screens, TVs, etc., the resolution is typically expressed in pixels.

Common display resolutions include VGA (640 x 480), SVGA (800 x 600), XGA (1,024 x 768), WXGA (1,280 x 720), SXGA (1,280 x 1,024) and UXGA (1,600 x 1,200).

Router

A device that allows you to create a home network, often between both wired and wirelessly connected PCs (or other devices). Technically, a router directly connects two networks together and handles the process of directing, or routing, information to the proper destination, typically through IP addresses. Some high-speed modems, such as cable modems and DSL modems actually function as routers because they connect one network (the Internet) with another--such as your home network. This is true even if it only consists of one PC because that one PC uses a different network address, which actually makes it a network.

While routers used to be sold primarily as standalone devices, nowadays routing capability is often built into products that combine multiple functions into one, such as wireless access point/routers, which are sometimes referred to as wireless routers. Current versions of Windows and Mac OS X also allow you to use your computer itself as a router.

RSS

Acronym for Really Simple Syndication, a mechanism for automatically delivering content from web sites. RSS, which can also be thought of as an extension to the HTML language used to create web pages (technically, it's part of XML or Extensible Markup Language), is also used for Podcasting, or sending audio content that can be played back on one of Apple's iPod digital audio players.

Web site creators can use special RSS "tags" in their web page and regular PC users can use special programs that "read" RSS to deliver the content from those web sites to the users. In other words, it's kind of like a specialized form of web browser. In fact, several web browsers can now "read" RSS, but it's also possible to use special RSS programs, some of which are generically referred to as news aggregators, to get access to RSS-delivered content.

SMTP

An acronym for simple mail transfer protocol, the standard typically used when sending (as opposed to receiving) e-mail messages. SMTP, which is a part of the overall TCP/IP protocol used to communicate over the Internet, technically involves rules and mechanisms for sending and receiving e-mail. However, SMTP  is virtually always paired with either POP3 (Post Office Protocol) or IMAP (Internet Message Access Protocol), both of which offer more robust e-mail receiving capabilities, such as having the ability to leave copies of messages on an e-mail server. SMTP is the method of choice for sending messages.

When configuring an e-mail account, you often need to know and enter both a POP3 (or IMAP) server name as well an an SMTP server name. If you have trouble sending e-mails, it may be due to a change in your ISP's SMTP server name.

Spyware

A type of computer application that secretly makes its way into your computer and records or reports back activities that occur on your PC. Many spyware applications, for example, track what web sites you visit and any ads that you may click on and send that information back to a database that records this information and uses it to target you with pop-up ads and/or spam.

Many spyware applications make it onto your PC in the form of trojan horses. These programs, like their historical namesake, hide themselves inside something else. So, for example, you may download music sharing software and find out that it also includes a spyware application as a hidden part of the installation. 

Spyware applications are becoming a bigger nuisance all the time and can typically only be removed via dedicated spyware removal applications such as Spybot Search & Destroy.

SSID

An acronym for Service Set Identifier, a means of uniquely marking data that's intended to be carried over a particular wireless network. Practically speaking, the SSID is the name of the wireless network and it typically defaults to the name and/or brand of wireless router you are using, e.g., Linksys, or Belkin54g. The SSID is broadcast out to anyone within range of the wireless access point and is visible as the name of an available wireless network.

One very minor way of increasing the security of a home wireless network is to turn off the broadcasting of the SSID. In that situation, someone would need to know the name of the network and manually type it in.

Streaming Media

Audio and video files that are played in real time over a network connection (typically via the Internet) are referred to as streaming media. In many ways, streaming media is analogous to broadcast radio or television in that when you turn a radio or TV on, you step into the "stream" of the signal at whatever point it happens to be (such as the middle of a particular program). Streaming media differs from standard media files in that they typically begin playing immediately as opposed t having to finish downloading them completely before a file plays.

Subwoofer

A specialized type of speaker that's used to produce very low frequency sounds, typically 120 Hz and lower. In surround sound systems, subwoofers are the .1 in a 5.1 setup. Unlike conventional speakers, subwoofers are not directional, meaning they can be placed anywhere in a room and the sound they generate can be heard (or more often "felt") from anywhere. In fact, some subwoofers have speakers in them  that point down to the ground.

Subwoofers provide an extra kick to bass sounds in music and help recreate the excitement of a theater for movies with sounds such as explosions, rumbling planes and ships and much more.

Surround Sound

A type of audio system that uses multiple speakers (usually at least 5) to provide a completely enveloping sound environment.  Surround sound requires both a source that can generate the separate audio signals that are sent to the individual speakers--typically an audio receiver--as well as the speakers themselves.

Surround speakers are often configured as 5.1, which means five main speakers and a subwoofer--a specialized speaker that handles very low frequencies. The five main speakers consist of typical left and right, as well as a center channel and two surround speakers, which are placed behind the main listening point in the room. The center channel typically provides dialogue in movies and TV programs that support surround sound and the surrounds provide ambience and much more. 

Surround sound is generally provided in the source material you view/listen to (such as a DVD), but many audio receivers can take a regular, two-channel stereo signal and "convert" it into surround via one of several popular audio processing algorithms, such as Dolby Pro Logic IIx.

TCP/IP

An acronym for Transmission Control Protocol/Internet Protocol, the format or "language", used to send messages over the Internet. Technically speaking, TCP and IP are two separate protocols: TCP handles making connections between two computers and transmitting data, and IP breaks up data to be sent into individual packets. Together, TCP/IP form a very robust protocol that may not always be the fastest way to get data from one point to another, but is very reliable and forgiving of problems that may occur on the network.

Most computer users never have to worry about TCP/IP and TCP/IP settings, although you occasionally have to deal with setting or adjusting an IP address. An IP address is simply a number (expressed in the form xxx.xxx.xxx.xxx, where xxx can be any number from 0-255) given to each device on a network so that data sent across the network from one computer to another knows where it needs to go.

TPM

An acronym for Trusted Platform Module, a hardware chip being built into notebook and desktop PCs that can be used to improve security. A TPM can be used in conjunction with software to improve security for logging into a computer (often in conjunction with other hardware devices such as fingerprint readers or smart card readers) as well as for encrypting files on the hard drive itself.

Windows Vista will include basic support for TPMs when it is unveiled next year, but other companies will also offer other software solutions that can take advantage of TPMs.

UPnP

An acronym for Universal Plug and Play, a standard used by PC peripherals to enable them to operate without needing to manually install driver software on any PC within a home network. With UPnP, which is built into Windows XP, devices that are connected to a network (or another device attached to a network) automatically "discover" the other devices on the network and announce their capabilities to those other devices. So, for example, a UPnP printer can instantly work with any PC attached to a home network, without having to install driver software on each machine.

UPnP is particularly useful for new media devices because they can easily become part of a home network. The PCs on the network can share files, such as music, photos and videos with UPnP-enabled media adapters, for example, without lengthy software configurations.

Unsharp Mask

A filtering effect found in several digital photo editing applications that--despite its name--actually sharpens an image that it is applied to. Unsharp mask works by increasing the contrast between light and dark areas of an image and increasing the sharpness of the  edges. Technically what it does is first blurs the edges in an image, then subtracts that blurred or "unsharp" section from the original.

USB

Acronym for Universal Serial Bus, a common interface standard found on both computers and other electronic devices. USB is primarily used to attach peripherals and other accessories, such as keyboards, printers, cameras, etc., to the main, or host, device. The original USB standard, sometimes referred to as USB 1.1, supports a data transfer rate between devices of 12 Megabits per second. The new USB 2.0 standard, which is backwards compatible with USB 1.1, supports up to 480 Mbps, or 40x faster. In order to achieve these faster rates you need both USB 2.0 ports and USB 2.0-enalbed devices. Faster USB ports won't make slower USB 1.1 devices go faster and conversely, slower USB 1.1 ports will only allow potentially faster USB 2.0 devices to work at the original 12 Mbps rate.

Both USB 1.1 and USB 2.0 support hot swapping, which means you can plug in or disconnect devices from the "host" even while it is turned on and running.

User Accounts

Modern operating systems, including Windows XP, Mac OS X and Linux are all based around the idea that multiple people can (and will) use a single computer. In order to accommodate this, the concept of user accounts were developed in order to let person "feel" as if the computer was his/her own. With a user account an individual has a username and password that he/she needs to type in order to log in to the computer. What that actually does is brings up their own customized settings, including their own documents folder(s), e-mail settings, web site favorites, etc.

Along with the concept of user accounts comes the requirements for different levels of control or "permissions". Rather than providing complete access to all users, different levels of permissions determine whether or not a particular user can install applications, apply updates, change system settings, etc. The most important account is the Administrator (in Unix systems, it's the Root User). At least one user needs to be set as an Administrator, but in some cases, it's possible to have more than one Administrator. Only the person who logs in as the Administrator can make important system level settings, install new applications and so on.

VOIP

Acronym for Voice Over Internet Protocol, a phone service that uses the Internet and Internet protocols to place regular phone calls. In a VOIP system, the audio signals from a regular telephone are converted into digital form, then broken up into small data packets and sent over the Internet to another device that reverse the process and enables you to have a normal phone conversation. In other words, VOIP services work much like a regular phone except the calls don't travel over traditional phone networks but over the Internet.

VOIP services let you keep the same phone number you currently have and let you call anyone in the world, typically for much lower rates than traditional phone service. In some instances, emergency services (calling 911) and information (411) can be a problem for VOIP system, but those limitations are being overcome very quickly.

White Balance

The setting used inside still cameras and camcorders that determines what the imaging sensor in the device considers white. Different types of light have different color temperatures and this, in turn, impacts the color of everything in that light. Fluorescent lights, for example, often give off an "orangish" tint and photos or video shot under that light often carry an orangish cast on them. In order to compensate, the white balance setting in a camera can be adjusted for different types of  light or, in some cases, be adjusted manually. The end result is that photos and videos can show a more accurate representation of the colors in a given lighting environment.

WiFi

An acronym for Wireless Fidelity, WiFi is the commonly used name to describe wireless networks that use 802.11 technology. The name WiFi doesn't distinguish between different "flavors" of 802.11, such as 802.11b or 802.11g, but incorporates all of them.

WiFi networks can be easily set up at home and are often found in public places such as libraries, schools and some retail stores.

Wiki

A piece of software that enables the creation of simple web sites in which visitors can edit the pages as well as read them. The concept of these Wikis (as sites which use this technology are called) is to create an interactive community in which visitors to the sites can contribute to them in a very simple manner.

Technically, Wiki software is a type of web server software. Users who want to interact with Wikis can do so through any standard web browser by clicking on links that permit the editing of the pages in a Wiki.

Worm

A type of computer application that secretly makes its way into your computer via one of many methods, including e-mail attachments and downloadable files, and  performs actions that you don't want it to do. Worms copy themselves automatically and then pass themselves onto other computers connected to either a local network or the internet. Some worms perform damage to files or settings on your PC, while others are merely annoyances, but all of them take up memory and other resources in your PC. Many worms spread themselves by looking up the e-mail addresses stored in your e-mail program's address book and then automatically sending themselves to everyone in that address book.

While worms and viruses are often considered one and the same, technically they are different in that viruses can attach themselves to other files, while worms typically exist on their own.

The best ways to avoid the impact of a worm are to install an anti-virus application, keep the anti-virus definitions up-to-date, and avoid opening questionable attachment files, even from e-mail addresses that seem to be from people you know.

WWAN

An acronym for Wireless Wide Area Network, a type of wireless connection that provides cellphone-like range to a data connection. Typical home wireless networks, or WLANs (Wireless Local Area Network), provide a usable range of a few hundred feet, whereas a wireless WAN could provide a range of nearly a hundred miles in a major metropolitan area. Speeds for existing WWANs have been similar to dial-up modems, but newer types of WWANs are promising broadband speeds.

Several different technologies are being discussed for WWANs, most all of which leverage existing cellphone networks and are sold by wireless carriers. Some examples include EVDO and EDGE.