Beginning Mac Programming/Beginning Mac Programming.bin/Open Me for REALbasic 3/REALbasic 3.2/Example Projects/Applications/DataCrab 2.0r1 Emulator/Fak-Paks/TechDict Fak-Pak

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        TechDict Fak-Pak loaded up. (2167 factoids)
100BaseT    This is an extension of 10BaseT that runs at 10 times the speed. It's theoretically capable of 100 Mbpstransmission speed. The drawback for some installations is that it requires more expensive Category 5 cable to run at highspeeds, where 10BaseT will run on Category 3, 4, or 5 cable.     •
10Base2    Refers to a type of Ethernet cable that has been largely phased out. It's also known as "thin net." Cable speedsare typically up to 10 Mbps.     •
10BaseT     This is a type of Ethernet cable topology that uses RJ-45 connectors and a star topology. It's also known as"twisted pair." Transmission speed is 10 Mbps.     •
128-bit Operating Systems    Operating systems may eventually be 128-bit. The ability to address 128 bits of memory spaceis something that may be necessary for huge databases, and will speed up operations. Of course, this will not happen untilafter there are some 128-bit chips to run them on.     •
128-bit Video Cards    At one time they claimed to be the fastest out there. 128-bit cards natively address 4 MB of memory,but most have been kludged so that they can run with 2 MB of memory. The makers of these cards are going on theprinciple that a bigger memory bus means better performance.     •
1394 IEEE standard    See Firewire.     •
16-bit Operating Systems    DOS and Windows 3.x are 16-bit operating systems. They are limited in complexity and sufferinstability and slow speed (compared to 32-bit OSs) when run on 32- and 64-bit processors like the 386DX compatible chipsand above.     •
2-tier architecture    This term refers to applications that have a code base (1-tier) separate from the database managementsystem (1-tier), such as using Delphi to interact with Microsoft SQL Server (1+1 = 2 tier), for example. The application coderesides on the "fat client" which is used to process data The problem with 2-tier applications is that they become complexand hard to support as the user base increases in size. What may be good for 50 people doesn't work for 300 people.     •
3-tier architecture    This architecture splits the user interface from the application logic. The server handles the databasemanagement and application logic. This works out to less complexity at the client and a more scalable application.Additional user interfaces can be added easily because the user interface is the only thing that resides on the client. Forexample, you can easily let customers view data from the Web without changing the application that lets your salespeoplework with their data. The three tiers are basically the application code that resides on the client, the database managementand logic, and finally the database itself.     •
32-bit Chips    (32-bit processor) see 32-bit processor     •
32-bit color depth    Anything that supports 32-bit color supports over 4 billion different colors. Generally, graphics cardssupport up to only 24-bit color because the human eye cannot discern between colors at that level, and you need a lot ofmemory on your graphics card to display 32-bit color at high resolutions. Color scanners, however, often go up to 32-bitcolor depth. This usually results in a better quality scan, even though the color difference between two pixels may not beperceptible.     •
32-bit Memory Chips    72-pin SIMMs are 32-bit memory chips.     •
32-bit Operating Systems    Windows NT, OS/2, and some flavors of UNIX are 32-bit operating systems. Windows 95 is a32-bit operating system running on top of a 16-bit operating system (DOS).     •
32-bit processor    This type of processor can run a 32-bit OS, such as Windows NT or some versions of UNIX. You can alsorun a 16-bit or lesser OS, but performance is not optimal. Intel's 386DX, 486, Pentium, and Pentium II are all 32-bitprocessors. So are all of AMD and Cyrix's 386, 486, 586 and 686 variants.     •
32-bit Video Cards    These are generally older cards that were only capable of addressing 1 MB of RAM.     •
56Kflex    This is one of the two competing 56 Kbps modem standards. It was developed by Rockwell and Lucent and hasmore market share than USR's X2 technology due to the fact that it is licensed to over 700 modem manufacturers.     •
64-bit Chips    (see 64-bit processor) see 64-bit processor     •
64-bit Memory Chips    DIMMs are 64-bit memory chips.     •
64-bit Operating Systems    Some flavors of UNIX are 64-bit operating systems designed to run on 64-bit chips. There areplans to port Windows NT to 64 bits so that it can run on the P7.     •
64-bit processor    This describes a processor that can run a 64-bit OS. The DEC Alpha is 64-bit, and Intel's Merced will be a64-bit processor. The 386, 486 and Pentium and Pentium II are all 32-bit processors, even though the Pentium has a 64-bitmemory bus.     •
64-bit Video Cards    Most current video cards have a 64-bit bus with their memory on them. 64-bit cards must have at least 2MB (or multiples of 2) of memory.     •
8 bits    Make up 1 byte.     •
8-bit Memory Chips    30-pin SIMMs are 8-bit memory chips. If you want to use them with a 32-bit chip such as a 386 or a486 you need to put four of them in at a time.    •
Access Speed    This refers to the average amount of time it takes for a floppy  drive, hard drive, CD drive or other drive to find any particular piece of data on a disk.    •
Accuracy    Accuracy is how close to the actual value you are. For example, if the number you are representing is 4 and you say it's 3, you are inaccurate by 1.    •
Accuracy/Precision    If the actual value is 4.321 and you say that it is 4.30, then you are precise to 3 places but inaccurate by .021. If a value is represented as a bullseye on a target, a group of guesses or measurements represented by closely grouped points have a high degree of precision. If that group is near the center, it is highly accurate as well. On a bullseye, think of accuracy as how close to the center your arrow hits, and your measurement of precision as how closely you can group your shots.    •
ACPI    (Advanced Configuration and Power Interface) This power management interface takes the power management out of the BIOS and gives control to the OS. Typically, a system's BIOS is only able to turn a device off after a certain period of inactivity. With ACPI, the user can instruct the OS to slow down the processor or enter sleep mode. This basically gives the OS, and thus the user, more control of power management.    •
Active Matrix    LCD panels that are active matrix have a sharper, brighter image than those with passive matrix screens. They can also continue to be seen at much greater angles off of central viewing.    •
Active Movie    This is a Microsoft technology used for streaming video and audio over the Internet. It is an ActiveX control.    •
Active Server Pages    (ASP) Microsoft created this technology and bundled it with their IIS Web server. It is designed to allow easy combination of HTML, scripts (such as Javascript and Microsoft's VBScript), and ActiveX. Active Server Pages promise to be more robust than CGI when handling large amounts of client requests.    •
ActiveX    Microsoft technology designed to enable easier multimedia on the Web. ActiveX controls can be used in Java to create multimedia effects. For now, that means that when you go to Web sites, buttons can light up and sound effects can play when you interact by clicking or moving the pointer over things. To see ActiveX on sites that support it, your browser must support it as well. Check out www.activex.org for more info.    •
ADSL    (Asynchronous Digital Subscriber Line) This is a new technology just starting to come out that is the phone company's answer to cable modems. It supports data speeds over 2 Mbps downstream (to the user) and slower speeds upstream (to the Internet). This technology should eventually supplant ISDN if it ever comes down to a reasonable price point.    •
AGP    (Accelerated Graphics Port) This is a special port that will begin to show up on motherboards in the second half of 1997. The port will bypass the PCI bus and allow much higher throughput from the graphics card to the processor for speedier 3D graphics. You will need special graphics cards to fit into this slot. It will not be compatible with current PCI cards.    •
Alpha Blending    This allows two objects to be blended together. This is primarily used for atmospheric and environmental effects. It allows such things as "fogging," where an image is rendered behind a "translucent" image, which creates the effect of looking though fog or looking down through a pool and seeing the bottom. It also allows Depth Cueing, which is the lowering of the intensity of lighting to make an object appear farther away.    •
Analog    Analog refers to a representation of a quantity that varies over any continuous range of values. Analog signals can be thought of as pure in nature and not processed. Thus, the debate over whether record albums (analog representation of sound) sound better than CDs (digital representation of sound). Think of nature as analog. Values are exact, but it is impossible to correct errors in reproduction.    •
Analog Control    An analog control changes value in non-discrete steps. You can tune an analog control to non-distinct values. In some cases, like for volume, analog controls are better. Have you ever used a digital volume control on a new TV, and one setting is too loud while the other is too soft? You just can't get it in between. However, for channel tuning where values change by fixed steps, a digital control is much better. You just don't need to get in between channel 4 and 5. Also see Digital Control.    •
ANSI    (American National Standards Institution) This organization represents the United States in the ISO (International Organization for Standardization). They work to develop coding and signaling standards.    •
Anti-Aliasing    This is a method used to better define higher resolution objects in lower resolution. For example, you would use anti-aliasing if you have two lines that are so close together that at 320 x 200 they look as if they are one double-width line and you want to represent them better. This is most noticeable when dealing with curves, such as circles. For example, if you look at a circle drawn in a simple paint program at a low resolution, you can see the "steps" the points take to make the circle. If you raise the resolution you'll notice the "steps" much less. If you use anti-aliasing, different shades of the circle's color are used to "fill in" the gaps caused by low resolution. A good example of this is Font Smoothing that comes with MS Plus for Windows 95.    •
Aperture Grill    See Slot Mask.    •
API    (Application Programming Interface) APIs allow you to program to a pre-constructed interface (the API) instead of programming a device or piece of software directly. This allows for faster development, since programming to a device's API is designed to be easier than programming to a device directly. APIs allow you to program without having intimate knowledge of the device or software that you are sending commands to. For example, the OpenGL API allows you to create 3D effects without actually knowing the innards of your video card.    •
Argument    This is what you have with your girlfriend when she wants you to stop using your computer so much. Actually, argument refers to the value you call a procedure with. For example, if you wrote a line of code that said "goto 140," telling your program to go to line 140, the argument is "140."    •
ASIC    (Application-specific Integrated Circuit) An ASIC is a circuit designed for a very specific purpose, such as the processors in PDAs or the chips on a motherboard chipset. ASICs contrast with more general-purpose devices such as memory chips or x86 processors that can be used in many different applications.    •
Aspect Ratio    This is the ratio of the width by the height on a monitor or television screen. Most TVs and monitors have a 4 x 3 aspect ratio. The screens are 4 units wide and 3 units high. A movie screen has an aspect ratio of 16 x 9 (about 5 x 3) and that's why we have letter-boxed movies. HDTV screens will also have a 16 x 9 aspect ratio, if they ever come out.    •
Asynchronous Communication    This method of transferring data does so without a specific timing mechanism between the two communicating parties. The party receiving data isn't expecting more data at any set interval.    •
ATA    (AT Attachment) More commonly known as IDE, the "AT" refers to the IBM-AT computer where this interface was first used.    •
ATA-33    An extension to the ATA interface (IDE) that will effectively double the top data transfer speed up to 33 Mbps. Also known as Ultra-IDE.    •
ATM    (Asynchronous Transfer Mode) A networking protocol designed to move multimedia data around with high reliability and speed. Some ISPs use ATM as the protocol for their backbones.    •
ATX Form Factor    The ATX form factor specification takes the original baby AT-sized motherboard, rotates it 90 degrees, and calls for a power supply with a side-mounted fan that cools not only the power supply, but also the processor and add-in boards. This new approach was designed to lower costs and provide better motherboard placement in an ATX case.    •
AUI    This is a synonym for the 10Base-5 Thicknet Ethernet standard.    •
Availability    This is a measure of how much time a network or a connection is running. Generally, the equation is: Time Running / Time Measured (time running divided by time measured). Thus, if you measured something for 20 minutes, and it was only up for 19 of them, you'd have 95% availability.    •
Backbone    A segment of a network that's often a higher speed than therest of the network and connects all the other segments. If you don'thave a fast backbone, your network will lag. That's why a lot of ISPs areconstantly restructuring their backbones.    •
Bandwidth    This is a measure, in some amount of bits per second, of theamount of data that can be sent over a particular cable, interface, orbus.    •
BASIC    (Beginner's All-purpose Symbolic Instruction Code) Thisprogramming language was developed in the mid '60s. The language wasconstructed of simple English-like commands that were run through aninterpreter, line by line, each time the program was "run." This causedBASIC programs to be slow. Now, compilers have been developed to speed upBASIC programs, and recent versions of BASIC can do anything that otherlanguages can.    •
Batch    A group of commands that are executed one at a time. Same asscript.    •
Baud    The measure of how frequently sound changes on a phone line. Thisused to be the measure of speed of modems because they worked by bruteforce and actually made a sound for each bit of information. Now, modemswork on a more sophisticated level. A 14.4 Kbps modem actually uses 2400baud, but can transmit 14.4 Kbps.    •
Bilinear and Trilinear Filtering    This is used to smooth flat surfacesby averaging the colors of adjacent pixels, which blurs them and removesblockiness when viewed up close.    •
Binary code    Binary consists of a string of bits, i.e. 01010111000000001    •
BIOS    (Basic Input Output System) This makes your computer speak thesame language as every other computer, making accessing video and thekeyboard standard.    •
Bit    This is the smallest unit of measure in a computer. It isrepresented by a 0 (off) or 1 (on). You can think of a bit as a switch.If it's in the on position, it's a 1, and if the switch is off, it's a 0.All parts of your computer communicate in bits if you go to the lowestlevel.    •
Bit depth    How many bits it takes to represent the color in one pixel.The larger the bit depth, the more colors you can display and the morepower it takes to display.    •
Black box    Anything that you put input into and get output from, butdon't know what's inside or how it works.BLOB (Binary Large OBject)    A BLOB is a data type used in a relationaldatabase that can contain any type of binary data, including sound,video, graphics, etc.    •
Boolean logic    This is the form of logic where every answer is eithertrue or false. Alternately, you can think of it as either 0 or 1, where 0= false and 1 = true.    •
Boot    This is a verb meaning to load. You can say thatyou are booting your machine, or that your operating system is bootingup.    •
BPS    (bits per second) This is generally a measure of how fast somedevice communicates, usually in thousands of bits per second (Kbps) ormillions of bits per second (Mbps).    •
Bridge    Bridges link two or more network segments that use the samenetwork technology. The network topologies do not have to be the same,i.e. you can bridge Ethernet and Token Ring. If the protocols are not thesame on segments, then you've got a router. Bridges are used to reducenetwork traffic, increase cable distance (by acting as a repeater), andalso to link dissimilar network topologies that run the same networkprotocol.    •
Browser    Most commonly used to refer to a software program used to lookat World Wide Web pages.    •
Bug    This is commonly an error in design or programming in a hardwaredevice or piece of software. The effects of a bug may be as harmless asan extra graphic on the screen, or as harmful as a system crash or lossof data. See also Feature.    •
Bus    A bus is simply a data path between devices. The computer's systembus is what peripherals use to send and receive data from the processorand main memory.    •
Bus mouse    A mouse that uses the smaller 6-pin connector instead of yourcomputer's serial port. Also referred to as a PS/2 mouse because of itsearly adoption by the IBM PS/2 series of computers.    •
Bus speed    This is a measurement, usually in MHz, of how many times datacan be transferred over the bus per second.    •
Bus Topology    This network topology has computers connected to a strandof network cabling that is connected to network repeaters at one end andterminated at the other. If you break part of the cable or remove theterminator, all machines on that segment lose communication with thenetwork.    •
Byte    Simply put, it's 8 bits. Think of it as a string of 1s and 0s thatrepresents a number from 0 to 255. For example '01100101' is one byte ofinformation.    •
C    This is a programming language developed in the late '70s. It became hugely popular due to the development of UNIX, which was written almost entirely in C. C was written by programmers for programmers and it lets you write code in sloppy ways that other, more structured languages do not. When you think of programming in C, think of driving a Delorean. It goes really fast, but it's a mess inside.    •
C++    This is an extension of the C programming language that adds object-oriented concepts.    •
Cable Modem    Cable companies are working to provide Internet access over coaxial cable. That's right, the cable that you plug into your VCR or TV. A cable modem accepts this coaxial cable and can get data from the Internet at up to and above 1.5 Mbps. However, it's only available from certain cable companies in certain communities.    •
Cache memory    Generally a small chunk of fast memory that sits between either 1) a smaller, faster chunk of memory and a bigger, slower chunk of memory, or 2) a processor and a bigger, slower chunk of memory. This is to provide a bridge from something that's comparatively very fast to something that's comparatively slow. Most computers have cache memory that holds some of the information from main memory. When the processor needs the information it takes it from the speedy cache instead of the slower main memory. Cache memory GREATLY increases the speed of a computer by storing data that is most often accessed.    •
Cat 3, 4, 5    See Category 3, 4, or 5 cable standards.    •
Category 3 cable standard    Cat 3 cable is certified to run at up to 16 MHz. You can achieve speeds of up to 10 Mbps on Cat 3 cable. This cable maxes out with standard 10 Mbps Ethernet.    •
Category 4 cable standard    Cat 4 cable is certified to run at up to 20 MHz. You can achieve speeds of up to 16 Mbps, such as with the 16 Mbps token-ring standard.    •
Category 5 cable standard    This is the latest and greatest copper wire standard. It uses an RJ-45 plug like Cat 3, and 4, and 4-pair wire, but it is certified to run up to 100 MHz and is suitable for 100 Mbps wiring standards. The guys that wired up my last office certified their Cat 5 wiring at up to 155 Mbps, so higher speeds are possible.    •
CAV    (Constant Angular Velocity) This refers to a spinning disk. As data is read from the disk, the drive motor spins at the same speed. For example, CD-drives that work at CAV will read data at 12x towards the center and 20x towards the edge, where the disk is moving faster.    •
CD-R    (Compact Disk Recordable) CD-R drives will record up to 650 MB of data onto specialized CD-R media. The media is expensive compared to the mass-produced CDs that software is generally distributed on, but cheap for the amount of data you can store on it. CD-R media is a WORM technology. You can Write to it Once and Read Many times, but you can't erase anything you've written. CD-R never took off as people expected it to, but it's still got plenty of life ahead of it.    •
CD-ROM    (Compact Disk Read Only Media) CD-ROM media is read-only media that holds 650 MB of data. It's generally accepted as the easiest way to distribute software. CD-ROM drives can also read music CDs even though they are in a different format than CD-ROM media.    •
CGI    (Common Gateway Interface) This interface allows scripts or programs to run on a Web server. All Web servers support CGI scripting. You can make a CGI script do pretty much anything a computer program can. Most commonly, they are implemented to control user interaction with the Web server on a Web site. You can use them to password-protect certain parts of your site, or save a user survey to a file on the server.    •
Channel    This refers to the group of resellers that supply most companies with software, hardware, and support. The channel is a force to be reckoned with, and it competes directly against companies like Gateway 2000 and Dell. A channel can also be a content container, like a television channel. You may be watching TV channels on the Internet someday.    •
CIR    (Committed Information Rate) This term is used by ISPs to represent an amount of data that you should, on the average, be able to draw through your connection to them. This is measured in kilobits or megabits per second.    •
CISC    (Complex Instruction Set Computer) Intel x86 chips are CISC chips because of the complexity of the instruction set. On the other side of the coin, you have RISC chips that use a reduced instruction set. RISC chips split big operations into lots of simple, tiny instructions that are processed very quickly. Some people argue that RISC chips have the edge. Several Intel competitors such as Cyrix and AMD use RISC chips with CISC converters to compete against Intel's chips.    •
Client/Server    Client server technology came about when computers began to cost less. Mainframes are very expensive, and didn't give users much personal freedom. The client/server model promised to change that scenario and it's much more popular today. Basically, a client computer with its own memory and hard drive communicates with a server whenever it needs data from the server. The client can run by itself without the server and communicate with different servers as it needs to.    •
Clock chipping    Synonym for over-clocking.    •
Clock Cycle    Think of a clock cycle as one tick of the second hand (but generally at a much higher speed). Computer clocks run voltage through a tiny crystal that oscillates at a predictable speed to give a meaningful timing method to the computer. One clock cycle doesn't necessarily mean that the processor does one operation. Today's high-end processors often complete more than one operation per clock cycle, and sometimes, in the worst cases, it will take several clock cycles to complete one operation.    •
Clustering    Clustering is an up-and-coming technology using two or more computers that function together as a single entity for fault tolerance and load balancing. This increases reliability and up-time in a client/server environment. One computer will sense when another computer is failing or getting bogged down and will take over its tasks.    •
CLV    (Constant Linear Velocity) In terms of disk drives, it means that the rate of data being read off of the disk stays the same from center to outer edge. To accomplish this, the drive motor speeds up and slows down as data is read from different areas of the disk. The linear velocity remains constant. An 8x CD-ROM drive that operates at CLV will read data at 8x anywhere on the disk, from the center to the outer edge.    •
CMOS    (Complementary Metal-Oxide Semiconductor) This is the common reference for the BIOS preferences in your computer. Actually, it is a low power version of a chip. The low power comes into play because it is what commonly holds your BIOS preferences through power off with the aid of a battery.    •
Coaxial cable    This is the original Ethernet cable. It consists of a single, insulated copper wire, surrounded by a copper braid or foil. The wire is then coated with plastic. Coaxial cable is used in bus topology.    •
COBOL    (COmmon Business-Oriented Language) This is a programming language developed in the '60s by several computer companies and the US Department of Defense. COBOL is still used today for programming business applications and COBOL programmers are a major source of the Year 2000 headache. In fact, many of them have come out of retirement to fix the mess they've made.    •
Code    A series of instructions that make up a program.    •
Code generator    A code generator is part of a compiler. It takes intermediate code and translates it into the final workable code in the target language.    •
Coily    Enemy of Q-Bert.    •
COM    (Component Object Model) This is a Microsoft specification that describes methods of communication between components. For example, if you were to drag an item over a window, the item and window would have some rules of communication that they would follow. Those rules are described in the Component Object Model.    •
Compiler    A compiler translates a computer program from one language into another, catching any errors in syntax along the way. Most commonly, you translate some high level language, such as C++ or COBOL, into optimized machine language. This form of compilation puts your programs into a form that your computer can understand without any translation, thus speeding them up.    •
Compression    Takes something large and makes it smaller. Compression generally comes in two forms, lossy and lossless. Lossy compression is best used on graphics files and sound files. It crunches down the data at a much higher ratio, at the expense of having an image or a sound that isn't quite the same as before it was compressed. In the best scenario the data takes up less space, but the person viewing the graphic or listening to the sound file will not be able to tell. Lossless compression squeezes data down so that at some later date it can be uncompressed and returned to its exact structure. Lossless compression is best used on data files and programs.    •
Computer    Technically, this is anything that inputs data, processes it in some way, and outputs it.    •
Control Program for Microprocessors (CP/M)    CP/M was THE operating system before IBM created the PC. IBM was shopping for an OS for the PC, ended up going with Microsoft, and Bill Gates created DOS. CP/M is not really used on anything but fossils at this point.    •
Convergence    The ability of the three electron beams (red, green and blue) in a CRT monitor to meet at a single point and produce one dot. If a monitor is mis-converging, you will notice shadows of blue or red around any white images. Often, this will occur in only some parts of the screen. Some monitors have convergence controls, but most do not.    •
Cookie    Web sites send these to your browser so that the site is customized based on your previous actions on that site. For example, someday UGeek may send a cookie to your browser to let us know whether you are a new visitor or if you've been here before. We'd check for that cookie the next time you come to our site and maybe we'd show you some different information if you're a repeat visitor. If you want to view your cookies, look for a file called "cookie.txt" on your hard drive.    •
Core    In UNIX systems this term is commonly used in reference to core dumps.    •
Core Dump    In UNIX systems, when a program crashes, it "dumps" out an image of the memory and registers so that you may go through and see what caused the problem. This is almost as useful as the Netware and Windows NT memory dumps (which is not very, if you can't taste my sarcasm).    •
CP/M    see Control Program for Microprocessors.    •
CPU    (Central Processing Unit) Think of this as the brains of the computer. When most people think of processors, they think of Intel. The Pentium and Pentium Pro are CPUs.    •
CRC    (Cyclic Redundancy Check) A mathematical calculation that produces a number that can be used to check the integrity of a file by regenerating the number and comparing the results.    •
CRT    (Cathode Ray Tube) This is one of the main components of monitors and TVs. A beam of electrons is shot towards the CRT and as they collide with phosphors on the inside surface, they produce light. Today, other technologies are performing better than the heavy and bulky tube monitors. LCD panels and projection units are both in contention, but they still can't come close to the low cost of a CRT monitor or TV.    •
CTI    (Computer Telephony Integration) Simply put, this represents the integration of your computer and telephone. Its serious uses include dial-up registration, fax-back systems, and other systems that record your information by telephone access. A simple use of this technology would be using your computer/modem as an auto-dialer so you don't have to push the buttons on your phone.    •
Cyberspace    This term was coined to refer to the vast expanses of the Internet. Just as space is infinite, the Internet is, well, pretty darn big. It just sounded cooler than "Internet" to the news media.     •
Daisy Wheel printer    A printer that uses a wheel with all the characters on it to produce output. These printers generally aren't used much any more due to the decreased cost of other printers that can produce graphics as well as text. The one good thing about a daisy-wheel printer is that the text is generally very crisp.    •
DAT    (Digital Audio Tape) This type of magnetic tape at one point threatened to supplant the normal audio cassette with a better quality alternative. Unfortunately, it never really took off due to idiotic licensing issues that kept its price high. However, the small tapes took off big in the computer industry. You can get DAT drives today that hold up to 8 GB of data. Audio DAT tapes are not compatible with data drives.    •
Data    Information. Any series of bits, characters or objects that has meaning. Data is stored and transmitted by computers.    •
Data type    This refers to the type of data that is being used in a computer program. Different types of data take up different amounts of space. Some common data types are integer, float (for floating point numbers), or string (for a text string). If a procedure is expecting one data type and it gets another, you usually get an error message or a crash.    •
Database    An ordered set of data.    •
DB-25    This is the name for the connector used for parallel ports on PCs.    •
DCOM    (Distributed COM (Component Object Model)) This is yet another Microsoft technology. It is a version of the COM that is designed to work across networks and, specifically, the Internet.    •
Desktop Case    A computer case designed to sit on your desktop. It's wider than it is tall.    •
Device Bay Interface Specification    This is a new specification designed to provide a simple and generic way of interfacing computers and their components. Device Bay devices will be about the size of a VCR tape and will interface via the USB or FireWire interfaces. Expect to see computers with this technology in 1998.    •
Diamondtron    This is Mitsubishi's answer to Sony's Trinitron. Instead of rectangular pixels, Diamondtron used diamond-shaped ones which supposedly offer crisper text.    •
DIB    (Dual Independent Bus) This is the bus architecture between Intel's Pentium II processor, memory, and L2 cache. One bus connects the processor to L2 cache and a second connects the processor to main memory. Having two buses instead of one increases performance over single-bus architectures. In addition the speed of the external L2 cache can scale up independently from the speed of the system bus. This allows for faster cache access. The final feature of the DIB architecture is a pipeline on the cache to the processor bus that allows multiple simultaneous cache requests.    •
Die size    Simply put, this is the two dimensional (length by width) measurement of a microprocessor. The thickness of the processor is not considered. For example, a die size may be 384 square millimeters.    •
Digital    Digital implies a value represented by a group of discrete steps. Some claim that digital representations of images and sound are more accurate; others that the translation of analog sounds and pictures into digital representations causes loss in realism. The bonus to digital reproduction is that if done well enough and designed to correct errors, digital reproduction can sound good over a long period of time. Records and tapes are analog, CDs are digital. Play a CD a million times and it should sound the same. Play a record a million times and it will degrade due to the weight of the stylus and the inherent friction involved in analog systems.    •
Digital Control    This is a control that doesn't directly cause a physical change in something, but rather sends a signal that a processor interprets. The processor then makes the change. An example of a digital control would be a television set with buttons instead of knobs. See also Analog Control.    •
DIMM    (Dual In-Line Memory Module) Very much like a SIMM except that they are larger and you need only one in place of two SIMMs. DIMMs are 64-bit memory devices, so you just need a single DIMM for a processer with a 64-bit memory path to work properly. DIMMs are becoming more and more popular.    •
DirectDraw    A set of APIs for Windows 95 and NT that allow programmers to directly access the video controller, allowing for faster graphics response.    •
DirectPC    TCP/IP over satellite. This is a system for going on the Internet by satellite at about 800 Kbps. Unfortunately, you also need a modem to be able to send anything to the Internet because the satellite is one way only.    •
DirectX    A Microsoft technology that works under Windows 95 and Windows NT 4.x. Basically, it's a set of APIs that allow programmers to access more directly sound and graphics capabilities of the computer allowing for, among other things, great games.    •
Disk Duplexing    See RAID 1    •
Disk Mirroring    See RAID 1    •
Disk Striping    See RAID 0    •
Disk Striping with Parity    See RAID 5    •
DLL    (Dynamic Link Library) This is a library of procedures that programs can call with input. The DLL produces output related to that input.    •
DLT    (Digital Linear Tape) A technology designed by DEC and sold to Quantum used for backing up huge amounts of data (up to 35 GB per tape without compression, 70 GB with compression). The drives are very expensive and so is the media, but they are bulletproof.    •
DMA    (Direct Memory Access) PCs have DMA channels that allow certain devices to directly access memory in order to speed up the process.    •
DMI    (Desktop Management Interface) This interface standard is designed to allow PCs to intelligently broadcast information on their system configurations and support remote management so that they can be managed more easily.    •
DMTF    (Desktop Management Task Force) This motley crew was assembled to create the DMI standard.    •
DNS    (Domain Name Service) This service maps TCP/IP numbers such as 123.12.4.245 to a more easily remembered name, such as www.ugeek.com. Thus, when you type www.ugeek.com into your browser, it goes out to the DNS server you specified when you installed dial-up networking (or TCP/IP services if you've got a nice connection) and asks for a matching TCP/IP address. If it finds a DNS entry for the name you typed in, you see our site. If not, it lets you know. Every domain name on the Web has a corresponding TCP/IP address that maps to the actual Web site. When you set up a site, you have your ISP add a DNS entry to their DNS servers. This entry gets replicated across the Internet in a matter of hours, and, once fully replicated, you can reach your Web site from any Internet connection in the world.    •
DNS Entry    The DNS routing tables are filled with DNS entries that map TCP/IP addresses to more easily recognized names. If your browser says it can't find a particular DNS entry, here are some possible reasons:    You may not be able to communicate with your DNS server. It may not be responding or your connection is broken. This is the case if you can't find anything.    If it really doesn't have the entry, there may be nothing mapped to that particular domain name address.    If the domain name was just put up, the entry may not have fully replicated to your DNS server. Remember, people can own a domain name (say bose.com) and not have an entry for it on any DNS server if they are not paying an ISP to host it.    •
Domain name    Domain names are used to represent more complex TCP/IP addresses. For example, we purchased the UGeek.com domain name so we could use it to represent our server's address. You purchase domain names through the InterNIC. They can be reached at www.internic.net. The fee for owning a domain name is currently $100 for the first two years, and $50 a year thereafter. Domain name purchasing is first come first served.    •
Domain Name Service    See DNS.    •
DOS    (Disk Operating System) This OS is what got it all started for PCs.    •
Dot Matrix Printer    This type of printer prints out little dots that can form graphics or characters. This type of printer was popular a while back because the only other choice was a daisy-wheel printer that didn't print any graphics. These printers are generally loud, producing a high-pitched buzzing sound, and they don't produce very good graphics. You'll still find them in bank machines and cash registers, but most users don't want anything to do with them.    •
Dot Pitch    The smaller the better, as it relates to monitors. The dot pitch is a measure of distance between phosphor dots of the same color on a CRT monitor. A high dot pitch generally produces a blurred and unclear picture. Smaller dot pitches produce a sharper, crisper image that stands up to close examination.    •
Double Buffering    This shows you that the graphics engine uses two layers, or buffers, to produce an image: one for display and one for rendering. Since the viewer only sees the finished image, this allows for smooth-motion animation. (Again, play Quake and watch as the background "jumps" across the screen as you turn your character.)    •
DPMA    (Dynamic Power Management Architecture) This architecture allows computers to have a variety of advanced power management features.    •
DRAM    (Dynamic Random Access Memory) The standard and cheapest memory available. The fastest DRAM is about 60 nanoseconds. This is the most common form of computer memory. It needs to be continually refreshed in order to properly hold data, thus the term "dynamic."    •
Drive Bay    Usually a 5.25"-wide 1"-tall hole in a computer case, suitable for the installation of some sort of drive. Some are exposed so that a removable drive (e.g., floppy, CD-ROM) can fit. Some are not exposed and are meant for hard drives, tape backups, etc.    •
Driver    A driver is software that works to communicate between an operating system and a peripheral. Think of it as a translator. If you use a crappy driver, your OS won't understand your video card and may become unstable and crash. Hardware manufacturers constantly update drivers to make them faster and more stable.    •
DS-0    (Digital Signal level 0) This is the signal used to carry a standard analog or digital phone line connection. 24 DS-0 connections can be carried on a T1 line. The speed of the signal is either 64 Kbps, or 56 Kbps if the eighth bit is used for signaling information    •
DS-1    (Digital Signal level 1) Synonym for T1.    •
DS-3    (Digital Signal level 3) Synonym for T3.    •
DS-4    (Digital Signal level 4) Synonym for T4.    •
DSP    (Digital Signal Processor) A DSP is a microprocessor designed to work with analog signals such as video or audio that have been digitally encoded. The DSP then takes these digital representations and performs operations on them. DSPs are used in video, sound, and modem technology. Intel's MMX instruction set is basically an attempt to make the Pentium processor line capable of DSP operations. This follows Intel's theory of putting all the processor work onto their processors. However, DSP chips will still be used in your PC.    •
DSTN    (Double-layer Supertwist Nematic) This is a form of passive matrix LCD screen. It is an improved version of the standard supertwist nematic passive matrix LCD screen where the display is divided into two sections and addressed separately to deal with slow switching speeds that result in poor visibility. See also passive matrix.    •
Dual boot    This describes a system that can boot to two different operating systems. Some OSs, such as Windows NT and OS/2, allow for dual booting when installed. Of course, you can also use other methods such as commercial programs that install a special boot partition that is capable of launching operating systems from other partitions. You can also boot to more than two operating systems on the same machine.    •
Dualscan    Refers to a passive matrix LCD screen that uses a better method of displaying graphics, producing a sharper, more vivid image than normal passive matrix screens.    •
Dumb Terminal    These are hooked up to mainframes, and are little more than a monitor attatched to a keyboard. All they are good for is running programs using the mainframe's hard drive and memory.    •
DVD    (Digital Variable/Versatile/Video Disc) Much like a CD-ROM except that it stores up to 12 times as much and is re-writeable. Although the industry claims that DVD really stands for NOTHING, I think otherwise. DVD is the successor to CD-ROM technology. It's the same size, but holds between 4.7    18 GB of data. The first wave of DVD drives will be read-only devices, but future versions will work with rewriteable media. The drives are finally starting to come out now, and in the consumer market they will eventually replace VCRs and Laserdisc players.    •
EBCDIC    see Extended Binary Coded Decimal Interchange Code.    •
EBIOS    (Enhanced BIOS) The EBIOS translates between the partition table limitations of a standard computer BIOS and the IDE limitations to provide up to 8 GB of storage space using the IDE interface. Your computer's BIOS has maximums of 1024 cylinders, 256 heads, and 63 sectors (8 GB). The IDE interface has a maximum of 65536 cylinders, 16 heads, and 256 sectors (128 GB). Put these maximums together (1024 cylinders, 16 heads, and 63 sectors) and you've got a measly 504 MB of data to work with. The EBIOS translates these limitations in such a way that you can actually achieve the BIOS max of 8 GB on one IDE device. Of course, this is just a short term solution.    •
ECC    (Error Checking and Correcting) Generally refers to memory chips, or motherboards that support this type of behavior in full-parity memory chips. ECC memory uses some extra memory on the memory chips for parity information and checks to see whether a memory error has occurred. If a minor memory error occurs, the ECC logic will handle it. With full-parity memory (one step below ECC), you will be alerted of a memory error and your system will stop. With non-parity memory, you will experience random results, usually crashing, and possible data corruption.    •
EDO RAM    (Extended Data Out RAM) This refers to the successor of DRAM. Most systems today support EDO RAM. It's a conceptually faster RAM chip that has small bits of SRAM cache built into it. It still runs at slow DRAM speeds ( <= 50 MHz), however.    •
EIDE    (Enhanced IDE) Allows for two IDE channels that can each support two devices in peaceful coexistence. It also allows for hard drives up to 8 GB in size and CD-ROM devices.    •
EISA    (Extended Industry Standard Architecture) 16-bit ISA was extended to 32-bits and they called it EISA. Pretty creative. But, really, it's generally used only in server machines, and it never caught on because of VL-Bus and PCI. It beats out VL-Bus and PCI because you can have a ton of EISA slots in one machine without any complex wiring. I saw a server box that had 14 of them. VL-Bus and PCI generally support fewer than four slots, and that's a problem if you want to install seven network adapters and five RAID cards. EISA makes it possible.    •
Enhanced Small Device Interface    (ESDI) This was a popular form of hard drive and controller before IDE took over the PC market.    •
Environment    Normally, this is your surroundings. In your computer, the environment is what a group of variables are set to. Think of it as your computer's surroundings.    •
EPIC    see Explicitly Parallel Instruction Computing.    •
ESCD    (Extended System Configuration Data) This is setup data that is stored in a Plug-and-Play-compatible system BIOS. It consists of the system resource requirements of legacy (non PNP) devices, and the last working configuration of Plug-and-Play-compliant devices. Plug-and-Play devices that have ESCD entries will use the same resources each time the system boots, as long as no new hardware has been added. This ensures a stable configuration. Plug-and-Play OSs such as Windows 95 have access to the ESCD, as you would guess if you've ever manually changed device configurations in Windows 95 (by using the "Device Manager").    •
ESDI    see Enhanced Small Device Interface.    •
Expansion Slot    Refers to any type of slot in a computer that you can plug an expansion card into. Generally, it's limited to ISA, EISA, PCI, and PCMCIA, but there are other types and there will be more in the future.    •
Explicitly Parallel Instruction Computing    (EPIC) This is Intel and Hewlett-Packard's invention, designed to be used on Intel's forthcoming Merced processor. It is a method for arranging instructions so that they are ordered to be explicitly parallel. That is, multiple instructions can easily be executed at once, assuming that the hardware supports it. Intel's Merced processor is designed to get the most out of instructions arranged in this manner.    •
Extended Binary Coded Decimal Interchange Code    (EBCDIC) This is a way of encoding 256 characters in binary, much like ASCII, but used mainly on mainframes. Most of the time, EBCDIC is only mentioned in translations between EBCDIC and ASCII.    •
Extended partition    This is a type of partition that is an extension of a primary partition. It's possible to have many extended partitions on a hard drive.    •
Extranet    An Extranet is an intranet that extends onto the Internet. Confusing? Yes. Extranets are external extensions of a company's intranet that allow certain people to interact from the Internet. Not all intranets are Extranets.     •
Fabless    This term refers to a company that produces chips but doesn't own a fabrication plant, or fab. These companies are starting to become more and more successful at creating chips and renting out other companies' excess fabs to produce their chips.    •
Fabrication Plant    A fab is a factory that takes raw silicon wafers and creates chips with them. Often, fabs are categorized by what micron process they use. For example, the Intel Pentium chip with MMX is produced in a fab with a 0.35 micron process. Fabrication plants cost billions of dollars to build and are outdated within years.    •
FAQ    (Frequently Asked Questions) This is a document that lists the most common questions about something (with the answers, of course).    •
Fast SCSI 2    This version of SCSI transfers data at 10 Mbps. The connections all contain 50 pins. See also Fast-Wide SCSI 2.    •
Fast-SCSI    Plain vanilla fast-SCSI never really existed. See Fast-SCSI 2    •
Fast-Wide SCSI 2    This version of SCSI upped the pin count to 68, effectively doubling the signal speed of Fast-SCSI 2 to 20 Mbps.    •
Fat Client    Today's fast PCs are fat clients. They've got lots of memory and big hard drives. They store information and run programs locally off of their hard drives. Fat clients usually work in client/server environments, where they leave the servers free to serve. As a rule, fat clients are much more customizable than thin clients.    •
FCC    (Federal Communications Commission) These are the people in the government who decide what's legal and illegal to broadcast, including what frequencies are allowed to be used by whom.    •
FDDI    (Fiber Distributed Data Interface) This is a fiber optic interface that allows data to travel extreme distances (many miles/kilometers) without signal loss. It is far superior to copper wire for data integrity as well. FDDI is often used to connect Internet, LAN, or WAN backbones together due to these superior properties.    •
Feature    A feature is something that a piece of hardware or software is designed to do. Many things that appear to be bugs are actually features. Often, a hardware or software developer will have to make a tradeoff in functionality that causes some undesirable effects. If they are aware of this and accept it, it is not a bug, but a feature.    •
Fiber Optic    A method of transmission alternative to copper. The way it works is by pulsing light down a strand of glass. These pulses represent binary code. So far, that's no better than copper. The advantage is that a single strand of fiber optic can carry thousands and thousands of different frequencies at once without data loss.    •
FIFO Buffer (First In First Out Buffer)    An area of memory that holds information in the order in which it was received until the computer has time to use it.    •
Firewall    This is a form of Internet security that stands between a private network and the Internet. It is like a wall in that it can prevent unwanted traffic from passing either way. Some firewalls have proxy functions built in. In fact, the distinction between a firewall and a proxy is often blurry. Add in the differences and similarities between a firewall and packet-filtering router and you've got one big ball of confusion. True firewalls generally support packet-filtering, proprietary application filtering, and some proxy functions.    •
Firewire    An up and coming serial technology that promises to speed data at 200    400 Mbps. This standard may eventually replace your serial ports, parallel ports, game ports, USB and maybe even SCSI.    •
FishNet    This is a type of stocking material that Joel likes to wear under his pants.    •
Flash BIOS    This BIOS contains a flash ROM chip that can be updated under certain conditions, but is otherwise static.    •
Flash ROM    A rewriteable ROM that doesn't lose its info when the power turns off.    •
Flat Screen    A CRT that is made more flat than a standard tube by using more than one electron gun. It is most useful to professionals who rely on the precision of their monitors. It is also better for the standard user because a straight light across the monitor looks straight.    •
Flat Shading    This is the most basic shading technique. The entire triangle is only one color. This causes the image to appear blocky.    •
FM synthesis    This is a method of creating music using frequencies to represent instruments.    •
Fortran    This is a high-level programming language, a bit more advanced than BASIC, but not quite as complex as C. This language refuses to die because it is so huge in the scientific research community. It's not a tough language to learn and it's fairly powerful. About 60% of scientific programming is done in Fortran.    •
Fractional T1    This term refers to using a theoretical "piece" of a T1 line, such as 128 Kbps, 256 Kbps or 512 Kbps worth of the 1.5 Mbps T1 line. Many ISPs offer fractional T1 as a lower-cost alternative to a full T1, and a higher-cost alternative to ISDN. However, if you check the prices it's almost always worth it to go for full T1. The phone company has to install a full T1 connection anyway, and you'll just be paying a bit more a month. Basically, since a T1 is only four wires, the full line is installed and the ISP will only allow traffic up to the limit you are paying for.    •
Frame Relay    A method of communication that can go from the speed of an ISDN to the speed of a T1 in increments. It has a flat rate billing instead of a per time usage. It connects by using the telephone company's network.    •
Free text search    This type of search allows you to give a fragment of a word and have it found in any part of that word. For example, doing a free text search for "the" could return "Thesis", "Blithe", and "Diphtheria."    •
FTP    (File Transfer Protocol) This is the method of moving files from system to system using TCP/IP.    •
Full parity    This refers to the ability to send and receive a signal at the same time. It can effectively double bandwidth, assuming that you can benefit from sending and receiving data at the same time. Most of the time, this doesn't happen, since you usually don't send AND receive large quantities of data at the same time. However, in the case of network servers processing large amounts of data, full parity network cards can bring advantages.     •
Gate    A gate is a tiny electronic switch. These switches, when linked together, can perform logical functions.    •
Gateway    The computer or device onto which the first hop needs to go to get out of your network. As you know a TCP/IP route uses many hops to get from here to there.    •
GDI    (see Graphics Device Interface) see Graphics Device Interface    •
GIF    (Graphical Interface Format) Invented by CompuServe for efficient transmission of graphics. The format can only support 256 colors, or 8 bits. The newer revision, 89a, allows for multiple images in one file to simulate animation.    •
Gigabyte    (1 billion bytes) There are a few different ways of getting to this number. No one uses the same exact number, but they are all around 1 billion. One way of deriving the number is by multiplying 1 byte by 1024 for 1 KB then again by 1024 to get 1 MB then that by 1024 for 1 GB. The variations come when people substitute 1000 for the 1024s.    •
GIS    (Geographic Information System) This is a system for capturing and manipulating data relating to the Earth.    •
GlidePad    A touch-sensitive pad about 2" x 2" that will track the touch of a finger. It is not a pressure sensor so there is no need to press down, only to touch. This device acts like a mouse for pointing.    •
Gouraud Shading    This method analyzes the color at each corner of the triangle and takes an average of the colors where the corners meet. This causes the triangles to "bleed" together, making for a smoother, clearer, more colorful image.    •
Graphics    The pictures that computers display. Not text, but just about everything else.    •
Graphics card    The graphics card is generally an add-in board that plugs into the motherboard. It sends signals out to the monitor to represent what should be shown on the screen. A graphics card can send only simple text, or it can be designed to represent intense 3D graphics.    •
Graphics Device Interface    (GDI) This is a standard set of programming functions provided by Microsoft for the production of graphic output in Windows. Microsoft provides these functions in its Software Development Kits. The functions are device independent, so you can use them on any graphics card as long as Windows is installed.    •
GroupWare    This term is used to describe any form of software designed to allow a group of people to easily share ideas and data. Examples include Lotus Notes, Novell GroupWise, and Microsoft Exchange.    •
GUI    (Graphical User Interface) Any system that uses graphics to represent the functions of a program. All Windows operating systems are GUI.    •
HAL    (Hardware Abstraction Layer) This is the portion of the operating system that lets programs deal with hardware directly. This allows programs needing more speed from the computer to bypass the standard OS calls to hardware. So instead of calling the Windows' API to draw a dialog box, you would go through the pain of actually drawing it out line by line: much faster, but much harder to write. This is of particular importance when writing games.    •
Hard Drive    A device that physically stores data in your computer. Much like a floppy disk, but the system is closed and the disks are hard (usually metal, although some glass versions have been developed). The closed system gives the possibility of more precision, so the drive is much faster and can hold much more data.    •
Hash table    A table that contains "hash values," generally used for speeding up searching algorithms on sorted data. For example, a hash table for a dictionary might contain all the letters of the alphabet and the page numbers where each letter starts. That way, instead of searching through from start to finish for each word, you just use the hash table and get a big head start.    •
HEL    (Hardware Emulation Layer) This provides software-based emulation of features that are not directly available in hardware.    •
Help Desk    If you've ever worked in an office environment, you've probably done some help desk work, or at least called them. The help desk is the support organization designed to take care of your computer and phone problems. They work long hours, get attacked by everyone, and get crappy pay.    •
Hertz    A rental company, formerly represented by O.J. Simpson. Also a measure of speed. One Hertz means one time per second, so one megahertz (MHz) means 1 million times per second. This is the common measure of speed for processors and electronic activities inside a computer.    •
Heterogeneous Data sources    This is a data-warehousing term that describes the idea of drawing data from several different (heterogeneous) data sources on different platforms and computers.    •
Hidden Surface Removal    See Z-buffering.    •
Hierarchical relationship    This relationship is one where elements at lower levels are submissive to elements at higher levels. Just think of a hierarchy, where the King is above the Duke, who is above a peasant.    •
High Color    The name given to 16-bit or 65,536 colors.    •
Hit    When a user requests an HTML document on the World Wide Web, the server records that request as a "hit." The problem with measuring "hits" is that some Web servers also count each graphic on that page as a hit. For example, if you look at a page with five images on it, some servers count that as five hits. For this reason, "hits" are a questionable measurement of how popular a website actually is.    •
Hop    A small jump. In reference to the Internet, the route that a computer needs to take in order to get its information from here to there. Think of all the main computers in the world that are physically connected (by T1 and T3 and M1 and such) as stones in a lake. To get from your stone to the stone on the other side you need to "hop" on a certain number of other stones. Same for communicating on the Internet.    •
Hot Spare    This refers to a drive in a RAID configuration that sits idle until one of the RAIDed drives fails. The hot spare then assumes the role of the dead drive. When the dead drive is replaced, you can make it the hot spare. (The old hot spare doesn't revert back because it's got data on it now!) Hot spares are most often used in RAID 5 configurations, but can also be used in RAID 1 or RAID 10.    •
Hot-pluggable    Same as hot-swappable, but also connotes a simple plug-in mechanism for easy swapping.    •
Hot-swappable    This type of mechanism implies that you can remove or add things while the system is running. For example, hard drives and power supplies are often candidates for this term. Normally, they come in special proprietary form factors in server machines and RAID boxes. If you've got mission-critical applications you want your servers to have as many hot swappable components as possible. Recently, servers have been introduced with hot-swappable PCI cards and buses.    •
HTML    (Hyper Text Markup Language) A standard language made for typesetting, currently up to Version 3.2. It is mainly used for creating documents on the World Wide Web. Included in the language are provisions for including pictures and links to other pages.    •
HTTP    (Hyper Text Transfer Protocol) The way the data in an HTML document is transferred. What it really is is what tells the program looking at the data what to use it as. So, a document coming in HTTP is read as an HTML document.    •
Hub    A central connection point. Standard terminology for a device that connects multiple computers in a network.     •
I/O    (Input/Output) This abbreviation refers to any operation in a computer where data is transferred in or out of the computer. I/O may seem like a vague concept, but it refers to the basic throughput power of a computer.    •
I2O    The I2O standard is designed to simplify and speed up I/O operations on servers. It will eliminate the need for different drivers for each OS, and for each SCSI card and network card. The speedup is achieved by using an Intel 960 chip on the server's motherboard to handle a lot of the I/O processing that would normally be handled by the processor or I/O subsystem.    •
IA-32    (Intel Architecture-32 bit) This is Intel's 32-bit instruction architecture that runs on their 386, 486, Pentium, Pentium Pro, and Pentium II chips.    •
IA-64    (Intel Architecture-64 bit) Intel's 64-bit instruction architecture that will feature EPIC and run on the Merced processor when it is released.    •
IDE    (Integrated Device Electronics) IDE is the standard hard drive interface for PCs. You can connect a maximum of two hard drives to an IDE connection or channel. IDE hard drives are cheaper than SCSI drives, but IDE is generally slower than SCSI and does not support sector re-mapping.    •
Impression    When a user looks at a page on the World Wide Web, that visit is counted as one impression regardless of how many images are on that page. Most access log analysis tools remove server requests that reference ".gif", or ".jpg" (image tags) from their analysis. This is the most accurate measurement yet developed. An impression could almost be called a "page look."    •
Inkjet Printer    The next generation of dot matrix printers. It uses a head that sprays tiny droplets of ink onto print material. There are three major benefits to this method: 1) it is quieter than standard dot matrix printers, 2) it is able to make smaller dots to make print look better, and 3) since the ink is in liquid form, it mixes better when printing in color. On the down side, they print slower than standard dot matrix printers, and since they do not print by impact, they cannot print carbon copies.    •
Input    Anything entered into a computer or system. This includes keystrokes, mouse movement, and talking into a microphone.    •
Instruction    The simplest direction that you can give to a processor. Programs are made up of these, but you usually don't go down to such nitty-gritty levels. An example of what a single instruction would do is incrementing a piece of data by one, or clearing a piece of data out of a register.    •
Intermediate Code    This is code that is generated by the first step in a compiler. Rather than translating code directly from one language to another, it first translates it to this more generic and easier to manipulate language and then spits it at the code generator, which creates the finished product.    •
International Telecommunications Union (ITU)    This is a Swiss organization that decides on international telecommunications standards. Currently, they are working on the 56K standard.    •
Internet    The global network of computers constantly connected to each other using standardized communications protocols, specifically TCP/IP.    •
Intranet    Local network of computers using TCP/IP as the standard communications protocol. Usually an Intranet features some sort of HTML content that you can use a browser to look at. Think of it as a mini, private Internet.    •
IP Address    The specific network address of a computer on a network using TCP/IP as its network protocol.    •
IRDA    (InfraRed Data Association) These people developed the IRDA port standard that transfers data through the use of infrared light. Of course, you must have two IRDA devices to get any real use out of this technology. Most notebooks today come standard with this port and some printers do as well. It's handy if you road warriors want to print a document and you've got all the right stuff.    •
IRQ    (Interrupt request) This is a gateway for devices to request time from the processor to do their jobs. For instance, every time you hit a key on your keyboard an interrupt is generated on the keyboard IRQ. This is mainly only a concern for PC users.    •
IS    (Information Services) This refers to the field of computer technology but has been replaced by the newer and sexier term, "IT."    •
ISA    (Industry Standard Adapter) The 8- and 16-bit original connectors used in PCs. They run at a bus speed of 8 MHz. You can plug ISA expansion cards into an ISA slot. Modems and sound cards are ISA cards due to their low bandwidth requirements.    •
ISAPI    (Internet Server API) This is an API proposed by Microsoft to replace CGI. Programs written to ISAPI are compiled as DLLs and stored in memory so they can be run faster than CGI scripts.    •
ISDN    (Integrated Services Digital Network) This is a digital line that is often used to connect to the Internet. It generally come in two flavors: one is a 56 Kbps version, which in actuality only uses half of the ISDN line's bandwidth; the other is the 128 Kbps version, which uses both the 56 Kbps channels on the line. However, that's only 112 Kbps--the other 16 Kbps are an 8 Kbps back channel of each line.    •
ISP    (Internet Service Provider) An ISP provides Internet access to people or corporations. ISPs generally have pools of modems awaiting dial-up connections. Smaller ISPs buy bandwidth from larger ISPs. There are two basic ways of connecting: one is to get a PPP or Slip account; the other is to get a UNIX shell account.    •
IT    (Information Technology) This term refers to the field of work dealing with computers and technology.    •
ITU    see International Telecommunications Union.     •
Java    This is a platform-independent programming language designed by JavaSoft. Java is much like C++, but includes some restrictions. Java mainly runs on Web browsers at the moment, but it can also run natively on operating systems or in a Java virtual machine.    •
Javascript    A simple scripting language designed by Netscape to be embedded into HTML documents. It is unrelated to Java.    •
JDAP    (Java Directory Access Protocol) This is the Java answer to LDAP. It really means Java implementation of the Lightweight Directory Access Protocol.    •
Joystick    This is an input device first found on arcade game machines, then home game systems, and finally on computers. It consists of any stick-like object that can be moved in four or more directions. Usually, there's a button in the vicinity of the joystick. Joysticks come in many shapes and sizes, but lately they have been replaced by cheap button pads in home gaming systems.    •
JPEG    (Joint Photographic Experts Group) This is a method of storing graphic images. It was specifically made for storing more than 256-color images. It compresses pictures much better than the GIF way (GIF is meant to store graphics of 256 colors or less). You can also set the amount of compression you would like for the graphic; however, the higher the compression the less quality the picture has. On the down side, even at 100% quality (or 0% compression) the graphic is not perfect. JPEG files use the extension ".jpg."    •
Jumper    A jumper fits on two metal connectors. It provides an electrical connection between the two wires to enable a semi-permanent hardware configuration. The Plug and Play initiative was designed to eliminate jumpers, but so far this hasn't worked out very well. Most add-in cards, hard drives, and motherboards still have many jumpers that users can utilize to make the devices act in different ways.     •
Karnaugh Mapping    A means to show the relationship between logic inputs and desired output. Generally, a truth table is mapped to a smaller, more workable grid of output values (1's and 0's). Karnaugh Mappings are often used when working with electronic circuits and trying to predict their output.    •
KB    see Kilobyte.    •
Kbps    (Kilo Bits Per Second) A measure of data transfer. A 14.4 Kbps modem transfers data at about 1.8 kilobytes per second or about 100 KB per minute.    •
Keyboard    The main input device on PCs, it consists of all the letters in the alphabet and the numbers 0 through 9. Usually, especially on computer keyboards, there are extra keys like cursor keys and function keys.    •
Kilobit    1024 bits (2^10 bits)    •
Kilobyte    1024 bytes (2^10 bytes)     •
L1 cache    (Level 1 Cache) The cache that's on the CPU, usually meant for holding instructions as they get executed. Sort of a death row for instructions.    •
L2 cache    (Level 2 Cache) This is cache memory that sits between the L1 cache of the processor and main memory.    •
LAN    (Local Area Network) A small isolated network at one office location. Most office computers are connected to a LAN, but may also be connected to the Internet, or a WAN.    •
Laptop    A computer small enough to fit completely on your lap.    •
Laser Printer    A printer that uses a laser to etch out what is to be printed. Toner goes on this etching and then the toner is heated to bond with the print material.    •
Latency    This is a measure of how long, on the average, it takes to get a response from something. This term usually refers to network response speed, and also to storage devices (hard drives, CD-ROM drives).    •
LCD Panel    (Liquid Crystal Display Panel) This is just a slab of specially treated glass which is used to sandwich liquid crystal. You can then send electricity through the treated glass to change the phase of the liquid, which then changes color. This is a low power way of displaying images.    •
LCD Projector    The same thing as an LCD panel, except it does not have any back so that you can put it on an overhead projector and shine a light through it.    •
LDAP (Lightweight Directory Access Protocol)    This is a client/server protocol for accessing a directory service. It is a lightweight version of the X.500 protocol.    •
Leased Line    A phone line that can be purchased from the telephone company that is yours only. With the assurance that you are the only one on the line you can work at faster speeds and stay connected 24 hours a day.    •
LED    (Light Emitting Diode) A piece of electronics that emits light when a current is passed through it. It does not work the same way as a light bulb so it does not have the problem of burning out. It also only emits a few frequencies of light so it is a specific color.    •
Legacy device    This is a type of device or peripheral that is not plug-and-play-compatible.    •
Legacy System    This is any old computer system that was set up before your time, and now continues to work and need support. Often, legacy systems are problematic to upgrade because the people that put them together aren't around any more. One great example is the year 2000 problem. Legacy systems are driving everyone nuts because no one programs in COBOL anymore, and lots of legacy code is written in COBOL.    •
LFN    (Long file name) Since DOS only allows eight letters then a period then three more letters, there is a separate distinction for it. Almost all other file systems allow for longer names. With Windows 95 now so prevalent, long file names have become common place. They can be 255 characters long, containing spaces or even periods. The only real restriction is no back-slashes.    •
Linux    Linux is a free personal computer operating system based on the UNIX operating system. It has almost all of the functionality of UNIX but has no official support. The code and the support come from the users and developers of the operating system.    •
Log    This is a record of events.    •
Log File    This is a file that records events. Many programs produce log files. Often, tech support will ask you to look at a log file to determine what is happening when problems occur. Log files usually record much "grittier" events than are shown to the user, like pieces of Windows 95 starting. You don't want to see each part of Windows 95 start, but it's good to have a log of it if something goes wrong. Often, log files will have the extension ".log"    •
Logical Parity    Fake parity that always agrees. In other words, when something checks to see if the data is in error the logical parity always says that it is not.     •
M2020 riser    This board holds a Pentium Pro processor and fits into a Slot 1 slot on a motherboard. This provides a sort of backwards compatibility of Pentium Pro chips with the newer Pentium II motherboards.    •
Mainframe    Basically, a large and powerful computer designed to be very fault tolerant. Historically, mainframes with lots of memory and disk space are hooked to a bunch of dumb terminals that can be used to access data on the mainframe, but can do nothing without the mainframe. See also, Client/Server.    •
MB    see Megabyte; also an abbreviation for Motherboard.    •
Mbps    (Mega-bits per second) This is a measure of throughput in millions of bits per second.    •
MDRAM    (Multibank DRAM) This is a form of graphics RAM created by MoSys that allows transfers of up to 1 GB/second. Tseng Labs' popular ET6000 2D graphics chipset uses this form of graphics RAM to help achieve its high performance.    •
Mechanical Control    A mechanical control is a dial or knob whose physical setting directly affects some measurement. For example, the power button on your PC is a mechanical control. By pushing the button you are physically making an electrical contact so that power may flow to your PC.    •
Megabit    (One million bits) 1,048,576 bits (that's 2^20 bits).    •
Megabyte    (One million bytes) This is 1,048,576 bytes (that's 1024 x 1024, or 2^20).    •
Memory    Chips in a computer that remember data. Also commonly referred to as RAM.    •
MHz    (Megahertz) One million hertz.    •
Microcontroller    This is like a scaled-down computer designed for a very specific task, unlike a desktop computer, which has many uses. An example of an application for a microcontroller would be a traffic light, or the chip that controls the suspension system of your new car.    •
Micron Process    This refers to the size of lines capable of being etched onto a chip. A fabrication plant with a .25 micron process can create smaller chips that consume less power, and can run faster than a fab with a .35 micron process.    •
Microprocessor    (MPU) This is a chip containing a large amount of gates. It contains the CPU.    •
Mid Tower case    A metal box about 2 feet high that has special fittings to hold computer components like drives, motherboards and such.    •
MIDI    (Musical Instrument Digital Interface) This is the way to connect musical instruments (traditionally a piano keyboard) to your computer. To connect them to your computer, you need a MIDI cable and a MIDI port. The MIDI port usually doubles as a game controller port on your sound card. Instead of recording the sound that comes from the instrument, it records the notes that are played. This can then be played back in a number of ways: its speed can be changed or its tone can be changed. The most interesting aspect is that it can be applied to different instruments.    •
Millisecond    (One thousandth of a second) Usually used to measure the access speed of hard drives .    •
MIME    see Multipurpose Internet Mail Extensions.    •
MIP Mapping    (Multum in Parvam--"many in few") This stores a copy of the bitmap used as a texture in different sizes to minimize the distortion caused by shrinking or enlarging the textures during perspective correction.    •
MIPS    (Million Instructions Per Second) This is a rating of how quickly a processor can process instructions. A processor rated at 100 MIPS can process 100,000,000 instructions per second.    •
Mirror    This can refer to many things in the land of technology. Most often, it is used to describe a method of redundancy where data is mirrored across two devices, whether they are physically separate devices or not. Basically, the same data is written to both devices, so if one device fails, the other can be used and the data will be fine. As far as disk drive redundancy is concerned, when drives are mirrored, they are in a RAID 1 configuration. See RAID 1 for more info.    •
MIS    (Management Information Systems/Services) This is the department at most companies that everyone loves to hate. These are the people that work with Information Technology.    •
Mission-Critical Application    This is any application that is critical to the proper running of a business. If this application fails for any length of time, you may be out of business. For example, an order-entry system may be considered mission critical if your business relies on taking lots of orders. You don't want your mission critical apps running on junky hardware--or software for that matter.    •
MMX    (Matrix Math Extensions / Multi Media Extensions) 64 additional instructions for matrix math operations that are commonly used to process multimedia data. A slight improvement of the Pentium and Pentium Pro chip designs that is supposed to make it easier and faster to deal with video and audio.    •
MODEM    (Modulator/Demodulator) A device to turn digital signals to analog ones and back again, so they can be transmitted and translated back to digital at another modem without loss. Used for communication through means of audio, telephone, CB, etc.    •
Moiré    An interference pattern that gets created when small dots are placed in a tight pattern.    •
Monitor    A device for viewing the output from a computer, traditionally a much more precise TV set.    •
Moore's Law    Former Intel chairman Gordon Moore is credited with predicting the trend that transistor counts in processors double every 18 months. This law has held true since the 1970s. The law can also be applied to other technologies and works frighteningly well with hard drive and memory chip density, processor speeds, processor power, and processor size (micron process). Try applying this law for the year 2010 from what we have today and you'll be looking forward to it.    •
Motherboard    The circuit board that your CPU, IO chips and all the peripheral cards plug into.    •
MotherGlass    The sheet of silicon that the wafers are stamped out of to make computer chips.    •
Mouse    A pointing device that uses a roller ball on the bottom to detect motion.    •
Mousepad    A pad that has a surface made for use with a mouse.    •
MP3    (MPEG 3) This is a compression standard for music. It enables you to fit over 100 full length songs on a single CD with almost no loss of quality. You can find MP3 players and MP3 files on the Web--you just have to look. The music industry is unhappy about MP3 files being swapped around and has shut down some sites that distribute them. The best place to find them is with the use of IRC chat.    •
MPEG    (Moving Pictures Expert Group) This is a format for compressing video in a format similar to JPEG. It works.    •
MTBF    (Mean Time Between Failures) This is a time normally given in hours that predicts the failure of a device. The larger the number the better.    •
Multi-Threaded    Some operating systems allow multiple parts, or threads, of a single process to run simultaneously. These OSs are referred to as multi-threaded. UNIX is a multi-threaded OS, as is Windows NT.    •
Multi-tier client server    This is a form of client/server application that uses the multi-tiered architecture.    •
Multi-tiered architecture    This is the most scalable application architecture (over 2-tier and 3-tier). This architecture refers to 4-, 5-, or even higher-tiered architectures. It is the most complex type of architecture, splitting the application and database management tasks into many discrete components. For example, take the 3-tier architecture and change it so that the application logic is separate from the database management system. This gets you to 4-tier architecture. With this structure, you can more easily change one of the tiers without compromising your entire application. To get to five tiers, you could move some of the application logic to the client to optimize performance.    •
Multicast IP    This is a form of TCP/IP being proposed that will allow for high-bandwidth transmissions (like television channels) to be broadcast over the Internet to all the routers in the world (possibly) that are connected to someone watching that channel. To see the benefit, think of 1000 people making separate connections to the USA network (if it were an Internet TV channel--give me some leeway!). Each packet of data sent out would have to be sent to 1000 people. Thus, you have 1000 conversations active between the USA network server and people's machines, each one saying the same thing. That's poor scalability. Now, imagine that in this fantasy network, we only have 10 routers with these 1000 people connected to them. In simplistic terms, you only have to send each packet to 10 places, and each machine downloads packets directly from the router it is connected to. Thus, the USA network server doesn't have to do much work to keep Gary Busey movies going to 1000 people at once, and the rest of the network isn't clogged with all 1000 conversations. However, there's lots of minute details that must be considered, such as how many channels are offered and how much router memory that takes up. How about if no one is watching? That's wasted traffic.    •
Multipurpose Internet Mail Extensions    (MIME) This refers to functions used for the attachment of binary files to an e-mail message. MIME is the most common group of functions used to make this translation, and allows us to tack on graphics, sound, and executable files to our e-mail messages.     •
n-tuple    ((pronounced en-too-pull)) This is a mathematical term for a finite sequence of n terms. For example, the set {1, 2, 3, 4} is a 4-tuple. The set {Frank, Jane, Ed} is a 3-tuple. Any time there is a list of n things in a certain order, you can think of it as an n-tuple.    •
Nanosecond    (One billionth of a second) Used most often to measure the speed of memory.    •
NC    (Network Computer) This is a concept that came from the old days of dumb terminals. They are supposed to reduce the cost of standardized computers in the office environment.    •
NDIS    (Network Driver Interface Specification) This spec was designed by Microsoft to allow multiple protocols to easily communicate with Network Interface Cards (NICs) without knowing anything about those cards. In theory, you just have to install the NDIS driver for the particular NIC and you can bind multiple protocols to it. Previously, you had to unload one protocol stack to load another. NDIS allows multiple stacks on the same card.    •
Network    This refers to a group of interconnected computers. The computers must be capable of transferring data to form a true network--you can't just weld a bunch of computers together.    •
Newsgroups    See Usenet newsgroups    •
Nibble    Four bits or half a byte.    •
NIC    (Network Interface Card) The NIC is an add-in board that enables a computer to connect to some form of computer network.    •
NLX    This is a form factor similar to ATX. The difference is that NLX machines contain a riser card that the other expansion cards are plugged into. This allows for a shorter desktop case.    •
Non-parity Memory    DRAM that has no error correction or tracking, called parity.    •
Normal SCSI    This term is commonly used to refer to non-wide versions of SCSI that interface with 50-pin connectors.    •
NOS    (Network Operating System) This is an operating system designed to run across a network. It refers to the operating system that runs on a server, not the client.    •
Notebook computer    A computer the size of a notebook. Usually smaller and lighter than a laptop.    •
Null modem    There really is no "null modem" per se, but usually a null modem cable. This is a cable that connects two computers together via serial port and allows them to communicate. Some hardware manufacturers of network hardware, such as hubs and routers, include serial ports for programming their devices. You use a null modem cable to communicate with these devices. It's basically a modem cable with a couple of connections reversed.    •
NVRAM    (Non-Volatile RAM) A small amount of RAM that stores information even after you turn off your computer. Used in modems (for storing your settings) and in hardware keys for protecting software.     •
Object    Objects can refer to the objects in object-oriented programming or the objects in OLE (Object Linking and Embedding). In OLE, an object is a piece of a document, a graphic, or some multimedia. In object-oriented programming, an object can be a spell checker or a piece of a graphics program used to draw squares or circles. Do you remember the crazy story people used to try to tell about a word processer where you could pick all of your favorite pieces (favorite spell checker, grammar checker, text editor, font manager, etc.) and piece them together to form the ultimate customizable word processer? Well, those pieces are objects.    •
Object Linking and Embedding (OLE)    Object Linking and Embedding    aka OLE. This is a standard for sharing data between applications. It has been around since Windows 3.1 and continues to get better. For example, if you cut a picture out of Paint and paste it into a word processor document, you are using OLE to properly put the data into your document. Of course, if it doesn't work quite right, you can blame OLE, or the programs use of it. OLE allows objects to be linked to and embedded in other documents. Linking creates a link to the actual object. Embedding puts a copy of the object into the document. You can usually access the program an object was created with in order to edit the linked or embedded object just by clicking on the object.    •
Object-oriented Programming    This term usually refers to programming languages that allow you to work with objects. These objects can contain not only data type and data structure information, but also information about how the object can be used by procedures.    •
Object-oriented technology    This refers to technology, usually programming languages, designed to work with objects.    •
OC12    see Optical Carrier 12.    •
OC3    See Optical Carrier 3.    •
OCR    (Optical Character Recognition) This is the technology that allows computers to "read" the text from physical objects. It requires a graphical representation of text to interpret. This usually comes from a scanned image.    •
OEM    (Original Equipment Manufacturer) This acronym is used to denote equipment that is sold to other companies or resellers for integration into systems. For example, a hard drive manufacturer may sell an OEM hard drive in bulk quantities and no manual or cables with the promise that it will go into full systems, or maybe external enclosures, and be resold. What often happens is that you can pick up OEM products at computer shows for low prices.    •
Office Suite    The set of software products that are required by an office. Most often comprised of a spreadsheet program, a word processor, a scheduler, and a presentation manager. Sometimes they will include a financial package and a database program. These are put together by a single company, so they are made to work with each other.    •
OLE    (see Object Linking and Embedding) see Object Linking and Embedding    •
Online    The term refers to anything that's on the Internet, as in "I've got this great online magazine for you to check out at www.ugeek.com."    •
OpenGL    (Open Graphics Language) This is a 3D graphics language developed by Silicon Graphics. OpenGL support is built into Windows NT. You can see some examples by checking out the NT screen savers. Some 3D graphics accelerators have OpenGL acceleration built in.    •
Optical Carrier 12    (OC-12) This stands for the 622 Mbps ATM protocol. Some large Internet providers are using OC-12 for their backbones.    •
Optical Carrier 3    (OC-3) Synonym for the 155 Mbps ATM protocol.    •
Optical Drive    A storage device that uses light to store data instead of magnetism. To write it (usually) uses a laser to change a tiny portion of an optical disk so that it can be read later by checking the state of that portion.    •
OS    (Operating System) The program that allows you to access the basic functions of your computer. It is the minimum software required to run a program. The best one by far is the MacOS.    •
Output    Anything that comes out of a computer or system. As in, "Watch out for that pile of OUTPUT on the sidewalk."    •
Over-clocking    This is the act of running a chip at a higher clock speed than it was specified for. Very often, chips are capable of running faster than they are specified for, and can be safely over-clocked.     •
P54C    This is the official part number for the Pentium processor from Intel.    •
P55C    This is the official part number for the Pentium processor with MMX technology from Intel.    •
Packet    A collection of information. It's often used to refer to the chunks of information sent over computer networks.    •
Packet Filter    This is anything that filters out network traffic based on sender's address, receiver's address, and the type of protocol being sent. Some routers support packet filtering, all firewalls do, and some proxy servers will as well.    •
Packet InterNet Gopher    (PING) Part of the standard TCP/IP suite of protocols that allows you to check your connectivity with other devices, or to check whether your own TCP/IP stack is working properly. Normally, you type in something like "ping 206.119.148.38," and you either get a response from that IP address or not. PING is extremely useful for debugging network problems.    •
Page Fault    This is not an error. It means that the computer had to resort to using the swap file as memory.    •
Parallel    Meaning in unison, or many things at the same time. Most commonly refers to a computer with multiple processors that can execute multiple instructions at the same time.    •
Parallel Port    The parallel port is found on just about all PCs. It's a 25-pin interface cable (DB-25) that is designed for connection to a printer. Normally, it will take up IRQ 7. In addition to printers, you can connect many other devices such as scanners and storage. Of course, the parallel port is slow. It can transfer data at a maximum speed of 512 Kbps.    •
Parity    Meaning that there is an equality. Usually for the purpose of safety, so that if one goes bad there is still the other.    •
Parity Memory    Not quite memory that has a twin, but instead, more like a summary. The parity does not exactly have a copy of the original, but rather enough information to verify the integrity of the original.    •
Partition    You can partition your hard drive by breaking it up into one or more pieces, or "partitions." Partition    •
Pascal    This is a programming language that was designed to teach computer science students the concepts of programming. It's almost like C for dummies. In fact, the two languages are very similar, but the stoic brackets of C are changed to happy and fluffy "Begin" and "End" statements. Also, many of the more complex functions of C are missing, but it's still a fully functional language. Borland uses Pascal as the basis for its Delphi programming language.    •
Passive Matrix    LCD panels that are passive matrix have a duller, dimmer image than those with active matrix screens. Visibility and clarity decrease at greater angles off of central viewing.    •
Patch cable    This is the common name for any 10BaseT network cable that is used to connect, or "patch," any two network ports.    •
Patch panel    This is a group of network ports stuck together for easy accessibility. Usually, this panel resides in a wiring closet or server room. Connections are made between this panel and ports on a hub to enable a network connection at a remote port. Each port on the patch panel is connected by a long patch cable to a remote port anywhere in an office that needs a computer hooked up to the network.    •
PC Card    This is a newer synonym for PCMCIA Card.    •
PCI    (Peripheral Connect Interface) This interface was designed to supplant the VL-Bus architecture and provide a standard slot with a reduced size for high-speed peripherals. It normally runs at 33 MHz on a PC, but can run faster. PCI slots are 32-bit slots, like EISA or VL-BUS, but in a compact form factor.    •
PCMCIA    (Personal Computer Memory Card International Association) Aside from winning the award for being the longest and most-annoying-to-pronounce technology acronym, PCMCIA is a credit card-sized interface card standard. PCMCIA cards are most commonly found in notebook computers. You'll usually find two slots on newer models. Two small slots can hold two Type I or II cards or one Type III card. Type III cards are usually mini hard drives. Type I or II cards are usually modems or network cards, but can also be sound cards, SCSI adapters, and any other interface you can imagine. It is possible to use PCMCIA cards on a desktop computer but you need to purchase special hardware that's not usually worth it, unless you've got some really special use for your cards.    •
PDA    (Personal Digital Assistant) PDAs are basically beefed-up organizers. They have small LCD screens, some form of pen or keyboard input, and software for organization, OCR, and contact management. Some have even more features, such as Web browsing or Internet e-mail.    •
Peripherals    Any device that is not part of the motherboard, aside from memory and the CPU. For example, video card, sound card, modem, hard drive.    •
Perspective Correction    This correctly alters the textures in a scene to give a sense that all the images on the screen converge on one central point way out in the distance. It's why things far away look smaller.    •
Petabyte    One thousand terabytes / one million gigabytes / one billion megabytes / one trillion kilobytes / one quadrillion bytes (approximately)    •
PGA    (Pin Grid Array) This is a form of chip with a group of pins in concentric rectangles, designed to fit into a PGA slot. Most x86 compatible chips are designed in this format.    •
PGA slot    This slot accepts a PGA chip. See PGA.    •
Pincushioning    This is one form of image distortion on a monitor. Good monitors have controls to deal with this problem. Basically, the top and bottom of the screen are wider than the middle (convex), or vice versa (concave). When corrected properly, the left and right side of the monitor screen are straight vertical lines.    •
PING    see Packet InterNet Gopher.    •
PIO    See Programmed Input/Output.    •
Pipeburst Cache    See Pipeline Burst Cache. This is an abbreviation, or contraction, for it, just like "ain't" is an abbreviation for "am not."    •
Pipeline    This refers to the technique of processing multiple parts of an instruction at the same time. Many processers have two or more instruction pipelines. Think of it as an automobile assembly line. As one instruction is executed, the next instruction is being decoded and the one after that is being fetched from memory. (i.e., Ellen welds the frame of one car, while Frank paints another one, and Jimmy puts the tires onto the finished frame of another car.) The pipeline is only as fast as its slowest member. (If it takes Jimmy an hour to put on some tires, then it doesn't matter that Ellen can weld the frame in 20 minutes. Either the line will slow down, or you need three Jimmy's for optimal performance.) The speedup you get from having a pipeline is about equal to the amount of pieces of pipe. It's slightly slower due to the fact that the first instruction executed begins to fill the empty pipeline. (Jimmy can't put on any tires if Ellen is still welding the frame of the first car through the line!)    •
Pipeline Burst Cache    This is a form of L2 cache that uses pipelining to speed data access by being able to feed data to the CPU at the same time it pulls data from memory. The burst mode also allows the cache to fetch additional data from main memory before the CPU requests it.    •
Pixel    The smallest dot that a computer can display at a particular resolution. Screen size is often referred to in pixels: 800 x 600, for example. This means that the screen is 800 pixels across and 600 pixels vertically.    •
Platform    This is a means of generically grouping like computers. Macintosh computers are a platform; so are PCs running DOS. It's not very specific, and multi-platform support can mean many things. If someone says to you "this application supports multiple platforms," ask them which ones they are talking about.    •
PNP    (Plug and Play) This is a standard that was supposed to make adding peripherals to your system as easy as plugging them in and using them. Its biggest contribution, aside from headaches, is the removal of jumpers from many devices.    •
Point to Point Tunneling Protocol    (PPTP) This is a remote access protocol that allows people to make a connection to easily connect to their local network through the Internet or some other large network. Conversations are kept private through encryption. See also Virtual Private Network.    •
POP    (Point Of Presence) This is a local telephone number through which you can access your ISP. The largest national ISPs have POPs all over the country.    •
Port    To port something, you translate the code for a program from one platform to another. You could port a program you wrote on a PC over to a Macintosh, for example. Port    •
Portable Computer    Technically, any computer that is self-contained to allow easy moving. Most often refers to a computer that can work away from an outlet.    •
Power Supply    A device attached to the case that converts 120 AC to DC at voltages that a computer needs to run. They come rated by wattage.    •
PPP    (Point to Point Protocol) The mode of transport used to connect a computer to the Internet via a dial-up adapter (a/k/a a modem).    •
PPTP    see Point to Point Tunneling Protocol    •
Precision    Precision is how well you define a value. For example, if the value you are representing is 4.321 and you say it's 4.3, you are precise to two places. Numerically, precision is the amount of decimal digits that you are capable of measuring.    •
Precision vs. Accuracy    See Accuracy vs. Precision    •
Primary partition    Primary partitions are partitions that are bootable. You cannot have more than four primary partitions per drive.    •
Processor    Short for Microprocessor. See Microprocessor.    •
Processor cycle    This is what occurs during one tick of the processor clock.    •
Programmed Input/Output (PIO)    This refers to IO standards on IDE hard disk drives. If you have a hard drive that supports one PIO mode, you need your interface to support it as well for maximum performance. The data transfer rates for the various PIO modes are: PIO mode 0    3.3 Mbps; PIO mode 1    5.2 Mbps; PIO mode 2    8.3 Mbps; PIO mode 3    11.1 Mbps; PIO mode 4    16.6 Mbps. Ultra IDE doubles the data transfer rate of PIO mode 4.    •
Protocol    This is the behavior that computers must follow in order to understand one another. Think of it as a language. If two computers don't use the same network protocol, then they cannot communicate.    •
Proxy    This is commonly a form of Internet security. You can use a proxy or proxy server to pass data between your internal network and the Internet. A machine on your network sends a request to the proxy. The proxy sends the request to a server on the Internet. Thus, it stands in for the computer on your network. The server on the Internet never knows that the request is coming from anywhere but the proxy. Thus 100 machines on your network could all access an Internet server and it would look like the proxy was making all of the requests. Some proxies have caching and site filtering built in.    •
PS/2    This is a PC made by IBM. It can run OS/2 and DB/2. Of course, it can run anything a normal PC can run, but it's just a nifty IBM naming convention that caught on.    •
PS/2 port    This is a standard serial port connector used to plug mice and keyboards into PCs. It's got 6 pins and is small and round     •
Q-Bert    A mid '80s arcade game that involved a fuzzy red creature jumping from cube to cube, trying to avoid a purple snake named Coily.    •
Quake    Quake is a revolutionary 3D, first person perspective game full of blood and gore. Designed by ID software, it only runs well on fast P5 chips or better.     •
RAID    (Redundant Array of Inexpensive Drives) A manipulation of SCSI technology that allows you to combine several hard drives for use as one. The benefits can be either speed increase or failsafe (so that if one drive dies or crashes you don't lose your data), or a combination of both.    •
RAID 0    Also known as disk striping, this form of RAID combines two or more hard drives into a single logical drive. Any data is written in blocks first to one drive, then the next, and so on. A RAID 0 configuration sacrifices redundancy for raw speed. The more drives you use the faster your logical drive will be. The space available on the logical drive is the sum of space on all of the drives used, assuming that all drives are the same size. If drives are of disparate sizes, RAID 0 generally only uses a piece of the drive equal to the smallest drive. Of course, if one drive dies, you lose all of the information on the entire RAID. Use RAID 0 with care.    •
RAID 1    There are two forms of RAID 1: disk duplexing and disk mirroring. Disk mirroring involves two hard drives that are on the same drive controller. The same data is written to both drives, so write operations are slower because you must write data to both drives. Read operations are the same speed, as if you only had one drive. Disk duplexing is much like disk mirroring, but each drive is on a separate controller. This speeds up the normally slow write operations and also adds a level of redundancy, in case one of your controller cards dies. With RAID 1, you get half the space you paid for because you're writing twice as much data.    •
RAID 10    This form of RAID was originally called RAID 1+0 and is now commonly referred to as RAID 10. This is basically a bunch of RAID 1 drives linked together with RAID 0. Hence, you get the speed benefits of RAID 0 with the redundancy benefits of RAID 1. The only problem is that you use a lot of drives to do it. Like RAID 1, you only get half of the space that you've paid for. Of course, it may be worth it if you can rest easier at night. RAID 10 is generally a bit faster than RAID 5.    •
RAID 5    A RAID 5 configuration utilizes three or more hard drives and stripes the data across them, much like RAID 0. The difference is that parity information is striped across the drives as well, so if you lose any one drive, the information can be reconstructed from the parity information. For example, with three drives, the first stripe is data (on drive 1), data (on drive 2), parity (on drive 3); then data, parity, data; then parity, data, data. This pattern continues. If one drive fails, you get a mix of parity and data on the remaining two drives and you can reconstruct all of the data. Of course, before the data is reconstructed, the RAID operates in "degraded mode" and is slow. To reconstruct the data, you must remove the failed drive and replace it with another. During reconstruction, the array continues to be slow. Once the RAID is reconstructed, performance returns to normal levels. RAID 5 performance is similar to RAID 0 performance, but a bit slower due to the parity information. Performance increases, like RAID 0, when more drives are added. With RAID 5, you get most of the space that you've paid for, minus one drive's worth. A common option with RAID 5 is the hot spare, where a drive sits idle until needed. If you lose a drive, the hot spare takes over and the RAID is rebuilt automatically. Of course, you still get the performance penalty during the rebuilding stage.    •
RAM    (Random Access Memory) The place in your computer that programs reside when running.    •
Raster Graphics    This form of graphics is probably what you are looking at now. Composed of pixels on a bitmap, it allows for solid colored objects and graphics as we know them. See also vector graphics.    •
RDRAM    (Rambus DRAM) The future successor to SDRAM, RDRAM was originally developed by Rambus, Inc. This RAM architecture is capable of speeds up to 600 MHz, where standard SDRAM tops out at about 200 MHz. Intel picked RDRAM to be the future of RAM for PCs. RDRAM is used in the popular Nintendo 64 game machine for its high-speed capabilities, necessary for the intense 3D rendering being done.    •
Read Only    Usually applied to a file or other kind of document. Means that the object cannot be written to, which means that you can't save any modifications you make to it.    •
Redundancy    In a redundant system, if you lose part of the system, you can continue to operate. For example, if you have two power supplies and one takes over if the other one dies, then that is a form of redundancy. You can take redundancy to ridiculous levels, but you spend more money.    •
Refresh Rate    How often something is rewritten or updated. The refresh rate of your monitor and graphics card can cause your monitor to appear to flicker if set improperly.    •
Removable Storage    This type of storage allows you to remove the actual storage media from a drive and replace it with other media. CD-ROM, floppy drives, Jaz, Zip, Syquest, and Bernoulli are all removable storage.    •
Rendering=> Determines how colors are used on each triangle.
Repeater    A device used to repeat a signal to send it further away or to many more devices.    •
Reseller    Anyone that buys computer equipment or software and sells it. In most states in the US, you need a reseller license to purchase goods without paying taxes, and then you are responsible for collecting and paying taxes on the goods you resell. The combined entity of all the resellers makes up the channel. Resellers usually buy goods from distributors and sell them to the public.    •
Resolution    How fine the pixels are. The higher the resolution, the more pixels that can be squeezed onto a screen, thereby giving the appearance that the pictures on your screen are smaller without losing any detail. Because the pictures are smaller you now have room to place more on your screen.    •
Rewriteable    Meaning that what was written can be erased so that it can be written to again.    •
Ring topology    A ring topology refers to a network that is connected on both ends to one source, with client machines hanging off of the ring. If you break the ring, all computers in the ring lose connectivity.    •
RISC    (Reduced Instruction Set Computing) RISC chips use a simpler instruction set than CISC chips to get their work done. This results in more instructions that need to be processed by the processor, but they are easier to process, so the chips can process more instructions per clock cycle than a CISC chip. Chip philosophers argue the benefits of RISC vs. CISC, but there is no clear cut winner. See also CISC for additional info.    •
ROB    (Radically Omnipotent Boy) A tall, bearded, long-haired person who is scarily intelligent and often dangerous (they have been known to be photographed with axes and chainsaws). A ROB normally likes to drive really fast cars and eat lots of pizza. ROBs also frequently contribute nearly 100% of the content of on-line Internet webzines.    •
ROM    (Read Only Memory) Memory containing a program, data, or information about the device that has been programmed onto the chip at the factory.    •
ROP    (Raster Operation) A raster operation refers to a set of low-level graphics operations in Windows, i.e., operations that deal with raster graphics.    •
Router    A device that bridges an internal network to another network. Take a ferry as an example: cars that need to go to the other side of a body of water (another network) need to use the ferry (the router). If they want to stay on their side, they simply don't go on the ferry. Also a device used to bridge a computer to a long distance digital communications network, such as ISDN.    •
RS-232    (Recommended Standard 232) This is the de facto standard for communication through PC serial ports. It can refer to cables and ports that support the RS-232 standard. "Hey, Jimmy! Why don't you take your RS-232 cable and stick it right up your RS-232 port!"    •
Runtime    This refers to the time when a program or process is running. When it's running it may need runtime libraries and have runtime variables with runtime values. It's also used to refer to runtime versions of software that include functionality of the software as the means to an end of running some other software, such as packaging a DOS program with a runtime version of DOS, so that you don't even need DOS on your computer to run the program.     •
Safe Mode    This is a Windows 95 mode that is automatically loaded if Windows 95 crashes during boot up. You can access Safe Mode anytime if you press the "F8" key when the screen says "loading Windows 95." This will bring you to a menu that allows you to boot into safe mode. Safe Mode is a special mode of Windows 95 that loads with minimal driver support. The purpose of it is to help resolve boot problems. For example, if you install the wrong graphics driver, Windows 95 crashes when it's loading. When you restart Windows 95, it will boot into Safe Mode and use the standard VGA driver with 60 Hz refresh rate. This will allow you to go to the Display Properties function and switch the video driver back to something that works. There is no reason to go into Safe Mode unless you are crashing during boot up or you are trying to diagnose a driver problem.    •
Sample    A small portion representative of something. Usual meaning a small amount of sound from an instrument, enough to reproduce the sounds of that instrument.    •
SAP    (Service Advertising Protocol) Used on NetWare networks to advertise available network services. For example, a NetWare server uses SAP to let other computers know that it's offering up some shared files.    •
Scalable    This adjective describes applications or systems that are able to scale to large amounts of users. For example, a database that completely locks out every other user when someone is using it is NOT scalable. The computer system that runs ATM and bank transactions must be highly scalable.    •
Scalar    A scalar value, in mathematical terms, is any single real number. The term superscalar is used by the semiconductor industry and refers to the ability to issue multiple instructions in a single clock cycle. Just think of scalar as a SINGLE number and you can see how this term was derived. See also vector and superscalar processor.    •
SCAM    (SCSI Configured Auto-Magically) This SCAM is actually a good thing. It allows SCSI devices to automatically (or automagically--don't make me barf) be configured with an ID number, even if they aren't assigned one. This makes adding SCSI devices much easier. You don't have to fool around with a bunch of jumpers or worry about assigning two devices to the same ID. Everything is done for you.    •
Scanner    A device used to copy an image from a physical source (e.g., photograph) into a computer.    •
Script    This refers to a group of commands usually stored in a file and run one at a time so that you don't have to type them in one at a time. Script is the newer, sexier term for batch. Don't talk about batch files anymore! It's all scripts and scripting languages. We're on the INTERNET, for goodness' sake!    •
SCSI    (Small Computer Standard Interface) A standard data pathway used mostly for hard drives and CD-ROM drives, but also a common interface for scanners and sometimes printers. Currently the fastest (and the most flexible) method of interfacing with hard drives. It comes in two major varieties: SCSI-2 or WIDE SCSI. Both can now be Ultra, which doubles the speed.    •
SCSI-2    This version of SCSI originally came in two varieties: Fast-SCSI 2 and Fast-Wide SCSI 2. Recent extensions to the SCSI 2 specification include Ultra SCSI, which comes in normal and wide flavors as well. It doubles the top data rates from 10 and 20 Mbps to 20 and 40 Mbps, respectively.    •
SCSI-3    This is not Wide SCSI. It is also not Ultra SCSI. In fact, the SCSI 3 specification does not exist yet. When it is created, it will probably use some sort of Fiber-channel interface. However, Ultra-SCSI is sometimes referred to as SCSI-3. Before Ultra-SCSI, people would refer to Fast-Wide SCSI-2 as SCSI-3.    •
SDRAM    (Synchronous Dynamic Random Access Memory) Like DRAM but arranged with a more efficient data pathway which allows for faster throughput.    •
SDX    (Storage Data Acceleration) This technology is being pioneered by Western Digital. The idea behind it is that slower drives such as CD and DVD drives will attach directly to larger, faster hard drives. They'll use a 10-pin connector between the hard drive and the other peripheral, as opposed to the 40-pin IDE connector. A portion of the hard drive will be used as cache for the CD drive or other device. This can speed up CD-ROM drives by 50%-300% depending on what operations are being performed. You will have to buy specialized hard drives and CD drives to take advantage of this technology.    •
Search Engine    This is typically a Web site that compiles and indexes a large amount of stuff on the Web and lets you search through it in some orderly manner. Search engines have many different strategies for collecting data and presenting it. If you can't find something in one, try another.    •
SECC    (Single Edge Cartridge Connector) The SECC is a processor cartridge designed to hold Intel's Pentium II and some external cache. It then plugs into a motherboard that supports Slot 1.    •
Secure Sockets Layer    (SSL) This is a protocol specified by Netscape that allows for "secure" passage of data. It uses public key encryption, including digital certificates and digital signatures, to pass data between a browser and a server. It is an open standard and is supported by Netscape's Navigator and Microsoft's Internet Explorer.    •
Serial    A means of operation meaning in series, or one after the other.    •
Serial Port    A data pathway that is usually used to connect modems and mice. Comes in 9- and 25-pin varieties, which are the same.    •
Server    A machine whose sole purpose is to supply information in its many forms, so that other machines can use it. See also client/server.    •
SGRAM    (Synchronous Graphics) RAM This is actually a form of SDRAM with some additional features to speed up 3D graphics. It is used on some graphics cards.    •
Shading    See rendering.    •
Shadow Mask    A thin sheet of metal with small holes poked through it used to focus the light from the electron beam on most CRT monitors. See also Slot Mask.    •
Silicon    An element commonly associated with glass. Called silica when bonded with oxygen. Sand and quartz is a form of silica. Not to be confused with "silicone." The main component of computer chips.    •
SIMM    (Single In-Line Memory Module) Those little memory cards we're used to putting into a computer as memory. It used to be that you needed eight or nine single chips to put into a computer to make a whole memory unit. Now a single card or two is what's needed.    •
SLIP    (Serial Line Internet Protocol) A protocol used to connect your computer to the Internet using serial connection.    •
Slot 1    This is a cartridge slot found on motherboards that accepts an SECC cartridge. It works with Intel's Pentium II chips.    •
Slot Mask    This form of mask is similar to a shadow mask, but instead of a sheet of metal with holes poked into it, it is a series of fine, vertically-aligned metal wires.    •
SMP    (Symmetric Multi Processing) This refers to a technology where a computer uses multiple processors to process different instructions at the same time, in separate processing units. It is a form of parallel computing.    •
Socket    Normally, it's where your limbs are attached to, as in "I'm going to rip your arm out of the socket." In network speak, a socket is composed of an IP address and a port number. For example, a socket could be "206.119.148.38 port 80." See also TCP/IP and ports.    •
Socket 7    This is a PGA socket designed to accept an Intel P54c or P55c (Pentium class) chip, an AMD K5 chip, or a Cyrix 6x86 chip.    •
Socket 8    This PGA socket is designed to accept an Intel Pentium Pro chip.    •
SOCKS    A protocol for communication through a firewall or proxy server. The SOCKS protocol uses TCP/IP sockets for communication. SOCKS is supported by Navigator and IE and allows them to communicate through proxy servers and firewalls, assuming the user has proper privileges to do so.    •
Sonictron    Viewsonic's answer to Sony's Trinitron. Like Trinitron, it uses an aperture grill instead of a shadow mask.    •
Sound Card    A peripheral device in the form of a card used for producing sound and music. Although PCs come with a speaker, it does not do a good job of playing music. As for reproducing sound, it takes most of the processor's power to produce only marginal sound, whereas a sound card does it effortlessly and produces a much better reproduction.    •
Spatial Database    This is simply a database that contains geographical or "spatial" information. For example, you could have a database of population by county in the United States, or amount of sales by state, or amount of employees per site.    •
Speaker Shielding    The ferro-magnetic shielding around the magnets of speakers that prevents interference with the monitor and stops damage to magnetic media such as floppies, Zip disks, and Jaz disks. Speaker shielding CAN damage MOs or CDs, however.    •
Specular Highlights    This allows for the appearance of light reflecting off an object. White or light-colored pixels are blended into darker areas to provide this function.    •
Spider    Also known as a Web crawler, a robot, Web spider, or sometimes a worm. A program that runs on the Internet, goes out to an URL (Web page), and requests all links that are referred to on that page. Robots learn as they go, building a database of links. They index based on meta tags in the HTML or the title, or just about anything else you can imagine. Usually, they come from search engines and are designed to keep the search engines current.    •
SQL    (Structured Query Language) This is a type of relational database that features data in rows and columns. Each row represents a record. Each column is a field. Most serious database solutions today use some form of SQL to store and access large quantities of data quickly and reliably.    •
SRAM    (Static Random Access Memory) Much more expensive and physically larger than DRAM, but much faster. The fastest SRAM has a latency of about 5 nanoseconds.    •
SSD    (Solid State Disk) The D in SSD is really a misnomer. SSD storage is basically a huge block of RAM chips that functions like a hard drive. SSD drives (obviously) are extremely expensive, but offer very high data speeds that are necessary in some applications. They can also be used as large caches on huge RAID subsystems.    •
SSL    see Secure Socket Layer    •
SSMP    (Simple Screen Management Protocol) This is a communications protocol for text-based terminals.    •
Star topology    This is a network topology that has network hubs at the center, with all connected computers linked back to the hub by a single cable. Thus, if one cable goes down, the rest of the computers can still communicate.    •
Stepping    This refers to the version of a chip. Microprocessors typically have many different steppings where performance is increased or minor bugs are fixed. The steppings are generally not touted as a new release of the chip, because chips are not as easily upgradeable as software. You would have to buy a whole new chip to upgrade it.    •
Streaming    This term is often used to describe technology that is capable of playing audio or video while it is still downloading. This saves you some waiting.    •
Superscalar Processor    This term describes a processor that is capable of executing more than one instruction during a processor cycle. Processors can do this by fetching multiple instructions in one cycle, deciding which instructions are independent of other instructions, and executing them. To do this, the processor must have an instruction fetching unit that can fetch more than one instruction at a time, built-in logic to determine if instructions are independent, and multiple execution units to execute all the independent instructions. Instructions that depend on the results of the previous instruction obviously can't be executed simultaneously with the instructions that they depend on. This type of instruction slows down superscalar processors. If all instructions are of this type, you get no benefit from the superscalar architecture.    •
Surge Protector    A specialized outlet that uses capacitors to keep spikes in the power supply from damaging electronic devices.    •
Swap file    An area of your hard drive that the computer uses for RAM. Although slower, it is usually much more abundant.    •
Switch    This refers to a hub that directs network packets to the port they are intended for, without broadcasting them to all connections. Switching is an alternative to moving to faster architectures. Switched 10Base-T can move data faster in some cases than a 100Base-T hub, because the 100Base-T hub takes up the hub's entire bandwidth with each packet sent.    •
Sybase    This company makes a SQL database product that competes with Oracle and Microsoft SQL Server. It's also the type of SQL that Microsoft based Microsoft SQL Server on.    •
Synchronous    Meaning that things happen at the same time. More commonly, used in electronics to signify something occurring at the set pace of a clock, much like a metronome.    •
System Software    This term can refer to all of the software that comes with a computer system, or more specifically, the operating system.     •
T1    Two pairs of copper wire that carry data at a rate of 1.544 Mbps. T1 lines are used to carry 24 DS-0 signals. They can be used to carry 24 phone lines or an Internet connection capable of 1.544 Mbps data transfer. See also fractional T1.    •
T3    28 T1 lines together make up a T3, which can carry 672 separate voice channels or up to 44.736 Mbps data throughput. Many large Internet providers brag of about having T3 backbones.    •
T4    Six T3 lines make up a T4 which carries data at 274 Mbps.    •
Tag RAM    This is a bank of SRAM that only holds addresses. Tag RAM is used to store addresses so that when the processor makes a call for memory, it first checks to see if the data is in the cache by looking for the memory address in the tag RAM. If it's there, it gets the data from cache. If not, it gets the data from main memory.    •
Tape Drive    A device that can store data on a tape. The advantage of storing data on a tape is that a tape can hold enormous amounts of data in a small and inexpensive package. On the down side, a tape cannot store the data indefinitely, and it is very, very slow compared to a hard drive.    •
TAPI    (see Telephony API) see Telephony API    •
TCO    (Total Cost of Ownership) This phrase was coined by the creaters of the Network Computer (NC) to describe the benefits of using a system that is more Mainframe and less Client/Server. Their logic states that NCs, although they may cost the same up front as cheap PCs, have a lower TCO than a network built on PCs.    •
TCP/IP    (Transmission Control Protocol / Internet Protocol) The TCP/IP suite first saw usage on the original Department of Defense Internet in 1983. Its first implementation was amazingly successful, and it is still THE protocol of the Internet. In fact, it has grown even more and is being used in private networks around the world. TCP/IP is a suite of communications protocols that allows communication between groups of dissimilar computer systems from a variety of vendors. There are other protocols that do similar things, like IPX or NetBEUI, but TCP/IP has the lowest overhead and is supported by almost everything.    •
Technographer    This person types into a computer exactly what a person speaking at a meeting requests of them. The output is displayed on a screen for all to see. The important thing here is that anyone can speak and ask the technographer to type in what they want. The technogropher doesn't type everything that is said, just what the speaker wants them to type. What is typed cannot be changed by anyone but the speaker, even if it makes everyone else angry and has nothing to do with the meeting. Do you see an opportunity for fun here?    •
Telephony    This is the science of audio communication through electric devices. It commonly refers to the many pieces of software that will make your $2,000 computer act like a $20 telephone. Of course, you can make this work for you with CTI. With CTI, you can make a $2,000 computer act like a $20,000 a year employee that works 24 hours a day.    •
Telephony API    (TAPI) This is an API for using telephony functions in Windows. For example, you can include TAPI instructions in your program that can dial numbers, receive calls, and interpret touch-tones.    •
Telnet    An old protocol for remotely logging in to another computer. It is one of the basic utilities for TCP/IP.    •
Terabyte    One trillion bytes, or one thousand gigabytes.    •
Texture Mapping    Pastes saved images, to be used as textures, onto triangle surfaces to improve realism. (Take a picture of a grassy field and code the program to use this picture to fill in your triangles on the floor--you get what looks like grass to walk on.)    •
TFT    (Thin Film Transistor) This is a synonym for the Active Matrix display. You'll often see screens referred to as "TFT-Active Matrix," or just "TFT" if they're low on space.    •
ThickNet    See AUI.    •
Thin Client    A thin client is similar to a dumb terminal in that it gets all of its information from the network. Some thin clients have their own memory, but lack a hard drive. They're basically stripped down computers that are supposed to lower the total cost of owning a computer. These computers are generally used in business or commercial applications.    •
ThinNet    See 10Base2    •
Thrash    - To move wildly or violently, without accomplishing anything useful. Also:    Paging or swapping systems that are overloaded waste most of their time moving data into and out of core (rather than performing useful computation) and are therefore said to thrash. Thrashing can also occur in a cache due to cache conflict in a multiprocessor system.    Someone who keeps changing his mind (especially about what to work on next) is said to be thrashing. A person frantically trying to execute too many tasks at once (and not spending enough time on any single task) may also be described as thrashing. From: Larry Crouch (Thanks, Larry!) Geek note: If you're dancing around to White Zombie, you're probably thrashing!    •
Throughput    Any measure of speed for data transmission.    •
Toner    Basically, it's ink in dust form. It is specially formulated to be sticky and to melt at a couple hundred degrees.    •
Toner Cartridge    When referring to laser printers, this is a cartridge that contains toner and the electrostatic drum.    •
Topology    This refers to the general structure of a network.    •
Tower Case    An improvement to the standard desktop case, it is flipped 90 degrees to accommodate more inside and to make it more convenient by allowing the case to be placed on the floor instead of the desk.    •
Trackball    Basically a mouse turned upside down. Instead of moving the whole pointing device, you simply move the ball on top. First seen in arcade games such as Centipede, but now used to replace mice where space is limited.    •
Transceiver    A device that translates between different network cables but maintains the same network topology. Thus, a transceiver could allow an AUI (Thick    Ethernet) NIC to work with a 10Base-T Ethernet network cable.    •
Transfer rate    This is the rate at which data is transferred in some amount of bits per second.    •
Transistor    An electronic device that acts like an electrically activated switch but has no moving parts so it can switch millions of times per second.    •
Trapezoidal Control    Control on better monitors that allows you to adjust the angles of the borders of the screen.    •
Trinitron    A technology developed by Sony to enhance the clarity of graphics on their monitors. The way this is done is by making the pixels more square.    •
True Color    The name given to 16.7 million color representation.    •
True Parity    This term has come about with the advent of logical parity. It simply means the original parity memory.    •
Truth table    This is a Boolean table that describes the way that a circuit reacts to input values by showing a complete set of possible input values with corresponding outputs.    •
Tuple    See n-tuple.    •
Turbo-Pascal    This is Borland's version of the Pascal programming language.    •
TWAIN    (Toolkit Without An Interesting Name) This is a standard set for scanners to allow them to have a standard interface to software. This allows the use of your favorite graphics package with your favorite scanner without worrying if one will support the other. As long as both are TWAIN-complaint they will work together. Check out www.twain.org for much more information.     •
UART    (Universal Asynchronous Receiver Transmitter) This is a chip that standardized serial communications. Its function is to change a byte into a standard sequence of electrical impulses.    •
Ultra SCSI    SCSI that communicates twice as fast as standard SCSI-2. Normal Ultra-SCSI transfers data at 20 Mbps, and Wide Ultra-SCSI transfers data at 40 Mbps. Similar to Ultra-IDE, Ultra-SCSI works its magic by transferring data on the up AND the down stroke of a clock cycle, doubling throughput.    •
UNC    (Universal Naming Convention) This is the name given for the naming used when one specifies: \\the sever\the volume\the path\then the file name of a file. So, a UNC will look like this: \\Myserver\Docdrive\Magazine\glossary.doc    •
UNIX    A lot like DOS, but a MUCH more powerful operating system. It was developed at Bell Labs and is now being developed by many other corporations. It is mainly used as a multi-user server for mainframes, although companies like Novell offer it for the desktop market as well.    •
UPS    (Uninterruptible Power Supply) This is a device that contains a battery and some circuitry to supply your computer with power for a limited time (depending on the battery) if there is any sort of interruption in the outlet power.    •
URL    (Universal Resource Locator) This is what is used to give Web addresses for HTML, VRML, WAV and other files. It simply contains the Internet name of the machine containing the data and the path to the file. Much like the UNC, except specifically for the Internet. The address also includes what protocol should be used.    •
USB    (Universal Serial Bus) A technology in the works that will replace the current way that some peripheral devices connect to your computer. It is much faster than serial and parallel communications. It is also much more flexible: it will be able to connect to possibly hundreds of devices simultaneously.    •
Usenet Newsgroups    Also referred to just as "newsgroups," Usenet newsgroups are a huge bunch of Internet discussion groups that replicate across the Internet every so often. If you get a bunch of people together and request a group for yourself, you'll probably be able to create it. Topics range from technical discussions and debate to flame wars. However, the most infamous use of the newsgroups is the distribution of binary pictures as text.     •
V.32    A standard naming convention used in determining modem communications, all starting with "V." This one is for specifying the Hayes standard of bi-directional 9600 baud transmission.    •
V.32bis    This is the standard that came after V.32 which increased the speed from 9600 baud to 14.4 KB baud.    •
V.34    This is the most recent dramatic improvement of modem communications. It has doubled the speed of the V.32bis standard to 28.8 KB.    •
V.34+    This standard was made by US Robotics to indicate that their modems are superior to a standard V.34 modem in that they run at 33.6 KB baud instead of the slower 28.8 KB baud.    •
V.42    This is the name given to the standard for transmitting at 2400 baud.    •
V.42Bis    This is not a speed standard like V.32 and V.34. It is an error correction and compression method that is hardware-based. Its major improvement comes from knowing when compression will be beneficial and when it will not be.    •
V.Everything    This is US Robotics' designation for their Courier Dual standard modems, which support all types of analog modem communications.    •
V.Fast    This standard was made between the time of V.32bis and V.34. It is also a 28.8 KB baud speed, but is not as reliable as the approved V.34 standard.    •
VB    (Visual Basic) This is a software product developed by Microsoft. Its purpose is to bring programming down to a drag-and-drop level to speed up development cycles. In many ways, that goal has been achieved. VB's main competitor is Borland's Delphi. Both programs offer similar functionality. The actual code for the program is BASIC and you can go in and edit the nitty-gritty if you want to.    •
Vector    A vector is a set of scalar numbers that refers to a point in space. Say, for example, you are in a two-dimensional space. A vector may be (5,6), which is 5 units across the X axis, and 6 units up the Y axis. See also scalar.    •
Vector Graphics    As opposed to raster graphics, vector graphics are composed of groups of colored lines. If you've ever seen those old Atari arcade games like Tempest, Battlezone, or Asteroids, that's vector graphics. At one point a company even made a home game machine based on vector graphics--it was called the "Vectrex." Nowadays, the only time you see things that look like vector graphics is when you are creating 3D models and you haven't rendered them yet.    •
Vertical market    This refers to an industry or group of companies that can be marketed to in a similar manner because they have similar needs. Common examples of vertical markets include the government, health care, and insurance.    •
Vertical Market Application    This is an application written specifically for a particular vertical market, as opposed to more generic multi-purpose applications such as office suites. One example is a program written for the insurance industry that computes insurance rates. Such an application is useless in any market besides the insurance industry.    •
Video Card    A device in computers that deals specifically with displaying to a monitor. Without one, you cannot see what's going on in your computer and may have to resort to the ancient method of using a printer as a monitor.    •
Virtual Memory    A part of your hard drive used to temporarily store what is in RAM. Usually used for little-used items, or when the required RAM is insufficient (since most every computer has more hard drive space than RAM).    •
Virtual Private Network    (VPN) This is a "virtual" network constructed by connecting computers together over the Internet and encrypting their communications so that other people cannot understand the communications. The benefit is that people can connect to the LAN from anywhere on the Internet. This allows easier connectivity and lower phone bills for travelling salespeople. They just sign up with a national ISP and call local POPs from their hotels as they travel the country and easily connect back to their company's local network. Microsoft's answer to VPNs is PPTP.    •
Virus    A program that makes unbidden copies of itself in order to proliferate. Usually plays a role either as graffiti or for malicious intent.    •
Visitor    When a user arrives on a website, he or she is considered one visitor regardless of how many pages he or she looks at.    •
Visual C++    This is a Microsoft product that is basically VB on steroids. It features a similar visual interface with drag-and-drop functionality, but the code is C++, which is more robust than BASIC. It's also much faster when compiled.    •
VL-bus    (VESA Local bus) This is a 32-bit extension of a 16-bit ISA slot. This architecture predated PCI and allowed users to break the bottleneck that occurred when the ISA bus slowed down graphics speed. It allowed speeds of up to 40 MHz, compared to ISA's measly 8.3 MHz. The fact that it had twice as many pins to transmit data helped out as well. VL-Bus was big on 486-66 machines, when it first came out, but was quickly displaced by PCI. PCI cards have some modest speed advantages and are much smaller. All VL-Bus cards were full-length cards.    •
VLAN    (virtual LAN) A VLAN is created when a bunch of physically connected ports are grouped together by network hardware that supports VLANs. These VLANs are each treated as completely separate entities and can only be joined together by a router. This scheme is useful for grouping departments together for security and minimizing network traffic.    •
VPN    see Virtual Private Network.    •
VRAM    (Video Random Access Memory) Memory made specifically for video applications (such as a video card). Much faster and more expensive than DRAM.    •
VRML    (Virtual Reality Markup Language) Virtual Reality Markup Language An enhancement to the HTML format used to make virtual worlds out of Web pages.     •
WAN    (Wide Area Network) Any network that spans more than one office, although some say it must span more than one building.    •
WaveTable    A bit of ROM on newer sound cards that stores standard sounds (as wave files) for instruments instead of generating them from FM sounds. This gives a much more realistic sound to music in games and MIDI files.    •
WFM    (Wired For Management Baseline) This is an Intel hardware specification that is designed to allow for compliance with easier management of desktop PCs in a networked environment. The specification calls for computers to be compatible with a pre-boot protocol that can be used to update the system or perform other management options. Also, the computer must be compatible with network/desktop management applications.    •
White Paper    This is a complete description of a particular technology, from overview to the nitty-gritty details. It is produced by the company that created that technology, as opposed to a FAQ, which can be created by anyone.    •
Wide SCSI    An improvement to normal SCSI that allows for faster throughput by increasing the number of pins used to connect the drive to the controller from 50 to 68. Wide SCSI doubles the throughput of normal versions of SCSI, but is generally more expensive due to the additional pins and marketing strategies. Of course, you are getting twice the performance, so what's a few bucks?    •
Windows Sockets    This is an API designed to help inconsistent TCP/IP stacks talk together and be accessed properly by Windows programs.    •
Wireless-Infrared/Radio Control    Meaning that the device you are using is not connected by cables to the main computer. If you have a radio mouse you don't have a wire connecting the mouse to the computer. Usually , you have a device that connects to the computer and the mouse sends radio signals to it so that it doesn't need to be attached. This is a much better implementation than the infrared method. Infrared is the way that standard remote controls for such things as TVs work. And as we all know, these need to be aimed at the device for which they are being used. So if you have an infrared keyboard you will need to make sure that it is pointed towards the receiver and that there is nothing in the way.    •
Wizard    An enhancement to programs that makes them easier to operate by guiding you through, step by step, what is required to achieve your purpose.    •
WMI    (Windows Management Instrumentation) This is Microsoft's answer to DMI. Apparently, they felt that DMI didn't fully exploit Windows and was therefore incomplete.    •
WORM    (Write Once Read Many) This is a type of drive/media that allows you to write to it permanently. However, you cannot erase what you've written. CD-R is a form of WORM drive.     •
X2    This is US Robotics 56 Kbps modem standard. It uses the fact that most ISPs are digitally terminated, and this eliminates one analog loop. Due to this fact, digital transmissions can remain more intact than previously, theoretically allowing for up to 56 Kbps data rates. See also K56flex.    •
X86    This is the last two digits of the PC CPU type. It originated with the Intel spec of the 8088, which then went to the 8086. Since then, increments have come by changing the first number to 80286 and 80386. The reason that the newer chips are actually named is because the numbers can't be copyrighted and Intel needed to distinguish its chips from competitors'.    •
XGA    This started out as IBM's term for a computer monitor resolution standard of 1024 x 768 pixels and 16-bit color. IBM released XGA monitors and graphics cards for their PS/2 computers, but unfortunately, the standard was interlaced and ran on 14" monitors. Nowadays, XGA just means 1024 x 768. Laptop makers often mention that their screens are XGA, meaning that they support that resolution.    •
Xmodem    This is a protocol for transferring files during direct dial-up communications. Developed by Ward Christensen in 1977, Xmodem has basic error checking to ensure that information isn't lost or corrupted during transfer. It sends data in 128-byte blocks. Xmodem has undergone a couple of enhancements: Xmodem CRC uses a more reliable error-correction scheme, and Xmodem-1K transfers data faster by sending it in 1,024-byte blocks.     •
Ymodem    This is also a protocol for transferring files during direct dial-up communications. So named because it builds on the earlier Xmodem protocol, Ymodem sends data in 1,024-byte blocks and is consequently faster than Xmodem. However, it doesn't work well on noisy phone lines. Ymodem has undergone a few enhancements: Ymodem-Batch can send several files in one session; Ymodem-G drops software error-correction, which speeds up the process by removing the overhead used by error-correction. This works because all modems since the V.32 era have error-correction built into the hardware.     •
Z-Buffering    (or Hidden Surface Removal) Tracks the depth of each triangle from the perspective of the viewer to ensure that objects behind others in a scene don't appear until the viewer has them in his/her line of sight. This is why you can't see through walls to what lies behind, but why you can play multiplayer Quake and have people at many different points in a level.    •
ZAK    (Zero Administration Kit) This is a software kit from Microsoft for Windows NT that can prevent various user actions such as installing software or changing desktop configurations.    •
ZAW    (Zero Administration Windows) This version of the Windows operating system from Microsoft allows for various easy administration and management options such as storing user software and settings on the network so that people can log into any machine on a network and retain the same personal settings. Basically, it turns your PC into an NC.    •
ZIF socket    (Zero Insertion Force socket) This is a socket designed to accept a PGA chip, such as most common CPUs produced today (e.g., Intel's Pentium, AMD's K6, etc.). The ZIF socket allows you to plug in a PGA chip with no pressure required. This is a big advantage because older sockets required you to push the chip in with equal force on all sides or risk bending the pins. It's not fun to bend pins on the new processor you just bought. I bent some pins once on a dual processor server without a ZIF socket, and luckily I was able to bend them back with some needlenose pliers because I didn't want to have to shell out another $1000.    •
Zmodem    This protocol has many error-correcting properties. It can detect if a bad block (of 1,024 bytes) has come through and ask to have it re-sent. If the transfer gets interrupted for any reason, it can resume from where it left off. It is slightly slower than Ymodem-G, but is much more reliable.     •