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Barrons Publishing Dictionary of Computer and Internet Terms 10th

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frame

206

frame

1.one in a succession of pictures in a video or animation. When displayed rapidly one after the other, successive frames give the impression of movement. See ANIMATION.

2.a boxed area in a web page. See FRAME, HTML.

3.a boxed area that is to contain text or a graphic (WORD PROCESSING,

PAGE LAYOUT SOFTWARE).

frame grabber an accessory device that takes an image from a video camera, VCR, or other video input and digitizes it, creating a bitmap image. A video image consists of frames (successive pictures) transmitted at the rate of 30 per second, and the frame grabber must grab and digitize one of them.

frame, HTML an area in a web page that scrolls independently of the rest of the web page. A web page can be divided into multiple frames. For example, one frame can include a navigation bar that always stays on the screen as the user moves around the text of the page that appears in the other frame.

Here is an HTML file that divides the browser window into two frames. The two files mentioned in it, navbar.html and main.html, are the source files for the separate frames.

<HTML>

<frameset rows=100%, *cols=35%,100%> <frame src=navbar.htmlname=NavigationBar

scrolling=auto>

<frame src=main.htmlname=mainscrolling=auto>

</frameset>

</HTML>

Here is file navbar.html, which produces the navigation bar in the left-hand frame:

<HTML><BODY>

<P><A TARGET=mainHREF=main.html#sec1> Section 1</A>

<P><A TARGET=mainHREF=main.html#sec2> Section 2</A>

<P><A TARGET=mainHREF=main.html#sec3> Section 3</A>

</BODY></HTML>

The following file, main.html, produces the main frame:

<HTML><BODY>

<H1><A NAME=sec1> Section 1</A></H1>

The rest of the text for section 1 would go here <H1><A NAME=sec2> Section 2</A> </H1>

The rest of the text for section 2 would go here <H1><A NAME=sec3> Section 3</A></H1>

The rest of the text for section 3 would go here </HTML></BODY>

207

free software

Figure 118 shows the appearance of this page when displayed by the browser. If the right-hand frame did contain a large amount of text, the user could scroll through it while the links on the left-hand side always stayed in the same place, making it easier to jump to other sections of the document.

FIGURE 118. Frames, HTML

framing error an error that occurs when an asynchronously transmitted character appears to contain the wrong number of bits.

See ASYNCHRONOUS; RS-232. Framing errors usually result from transmitting or receiving at the wrong speed.

free (describing Windows versions) not containing the extra error checking and debugging code that would be in a CHECKED version. Most computers run a “uniprocessor free” version of Windows, which is a version that runs on a single CPU and does not contain extra error checking. Contrast

CHECKED.

free software several kinds of computer software that can legally be copied and given free of charge to other users:

1.Public-domain software. This is software that is not covered by any kind of copyright. Few substantial public-domain programs exist, but the term public-domain is often used incorrectly to refer to other kinds of free software.

2.Software that is copyrighted but is distributed free with permission of the copyright owner. Two famous examples are the Linux operating system and the TEX typesetting program (see LINUX; TEX). Many UNIX utilities are also in this category.

3.Shareware. This is copyrighted software that can be distributed free to anyone, but that requests or requires a payment from satisfied users directly to the author. Shareware is often misleadingly described as “free.”

Free Software Foundation

208

Free Software Foundation see GNU.

Freescale the company that was formerly the microprocessor division of Motorola. See MOTOROLA.

freeware see FREE SOFTWARE.

freeze date a date after which the specifications for a software project cannot be changed. See SOFTWARE ENGINEERING.

freeze up to stop responding to input; to HANG. A frozen computer shows no activity on screen or on the front panel of the computer system and will not respond to the keyboard. Many times, the mouse cursor disappears. In Windows, control can often be regained by pressing Ctrl-Alt- Del and letting the operating system close the offending software. Macintosh users can often escape from a frozen program by pressing Option-Command-Esc and then selecting the FORCE QUIT button.

friend a fellow user of a SOCIAL NETWORKING SITE with whom you have some sort of relationship. Usually, both users must confirm that they want to be friends, and there are restrictions on contacting or viewing personal information of other users if you are not friends.

On social networking sites, “friends” are often just a contact list of passing acquaintances, and the term rarely indicates a close relationship.

friendly name the most familiar or meaningful of several names denoting the same thing. For example, a networked printer might be known as \\gizmo1\ttya-lj4 and as Office Printer. The latter is its friendly name.

front end a computer or a program that helps you communicate with another computer or program. For example, supercomputers usually do not communicate with their users directly; instead users submit programs through another computer called the front end.

front side bus see FSB.

FS online abbreviation for “for sale.”

FSB (front side bus) the BUS by which a CPU communicates with its fastest input-output devices. It is rated for speed in megahertz (MHz) or million transfers per second (MT/s). The latter rating is higher because there is usually more than one data transfer per clock cycle.

FTP (File Transfer Protocol) a standard way of transferring files from one computer to another on the Internet and on other TCP/IP networks. (See TCP/IP.) FTP is also the name of any of various computer programs that implement the file transfer protocol.

When you connect to a remote computer, the FTP program asks you for your user name and password. If you do not have an account on the computer that you have connected to, you can use anonymous FTP to retrieve files that are available to the general public. In that case the pro-

HALF DUPLEX.
INTERNET; PROTOCOL; WORLD WIDE WEB.

209

full duplex

cedure is to give anonymous as your user name and then type your e-mail address in place of the password. Also remember to use the command binary if the file you are transferring is anything other than plain ASCII text. Figure 119 shows an example of an anonymous FTP session.

C:\> ftp

ftp> open ai.uga.edu

Connected to ai.uga.edu FTP server. ftp> user

User name: anonymous

Password: yourname@your.site.address

User ’anonymous’ logged in. ftp> cd /pub/pc.utilities ftp> binary

ftp> dir pkzip.exe ahed.zip pred.zip

ftp> get pred.zip

pred.zip transferred, 17895 bytes in 2.5 seconds ftp> quit

FIGURE 119. FTP session (user’s commands are in italics)

You can also retrieve files by FTP using a web browser. For example, to retrieve the file whose name is filename in directory pub/directoryname on host ftp.cdrom.com, give the URL as:

ftp://ftp.cdrom.com/pub/directoryname/filename

If you need to specify an account name and password, do this:

ftp://userid:password@zzzzz.com/directoryname/fiLename

Most browsers will prompt you for the password if you leave it out. Ordinarily, FTP does not work through certain routers and firewalls.

For the solution, see PASSIVE FTP.

See also

FTP site a computer that makes files available for downloading by FTP.

FUD (slang) (fear, uncertainty, and doubt) the tactic of trying to make customers afraid of adopting a rival product by creating doubts about its future.

full adder a logic circuit that accepts three one-digit binary numbers (two addends and one digit carried from the previous column) and produces two outputs, a sum output and a carry output. See BINARY ADDITION.

full duplex communication in two directions at the same time. For instance, an ordinary telephone is a full duplex device; you can hear the other person while you are talking. Contrast

BOOLEAN QUERY; SEARCH ENGINE.

full-text search

210

full-text search the act of searching through every word in a set of documents to retrieve information you are interested in. This is a slow but thorough way to use a computer to search through web pages, court records, scholarly journals, or other material to retrieve items that you are interested in. See also

function

1.(in mathematics) a value that depends on one or more arguments in such a way that, for any particular set of arguments, the function has only one value. For example, the positive real square root of a number is a function of that number. The sum of two numbers is a function of the two numbers. A function need not exist for all possible arguments; for example, negative numbers have no (real) square roots.

2.(in computer programming) a subprogram that acts like a mathematical function: given a particular set of argument values, the function returns a unique result.

In C, C++, and Lisp, all procedures (subroutines) are called functions, though they need not return a value (see PROCEDURE; VOID). In Java and C#, procedures and functions are called METHODs and are always attached to classes, though not always to specific objects.

function keys (F keys) keys labeled F1 to F12 on PC keyboards, and similar keys on other kinds of computers. Their function depends on the software being run. See also PROGRAMMABLE FUNCTION KEY.

fuser in a laser printer, the hot roller that warms the toner particles that have been deposited on the paper, to melt them and make them stick. See

DRUM.

fuzzy logic a formal system of reasoning developed by Lotfi Zadeh in which the values “true” and “false” are replaced by numbers on a scale from 0 to 1. The operators and, or, and the like are replaced by procedures for combining these numbers. See BOOLEAN ALGEBRA.

Fuzzy logic captures the fact that some questions do not have a simple yes-or-no answer. For example, in ordinary English a 6-foot-high man might or might not be described as tall. In fuzzy logic, a 6-foot man might be tall with a truth value of 0.7, and a 7-foot man might be tall with a truth value of 1.0. A problem with fuzzy logic is that there is often no clear way to come up with the numbers that are used as truth values. For an alternative, see DEFAULT LOGIC.

Fuzzy logic is often used in expert systems; it nicely bridges the gap between logical inference and mathematical modeling. See CONFIDENCE FACTOR; EXPERT SYSTEM.

FWIW online abbreviation for “for what it’s worth.”

211

gamma

G

<g>, *g* e-mail abbreviation indicating a grin.

g2g chat-room abbreviation for “[I’ve] got to go.”

gadgets in Windows Vista and in Google Desktop, add-ons to the sidebar often done by developers other than Microsoft or Google, which provide additional functions such as displaying the weather in your area or providing a place for notes.

gain the amount of amplification in an audio amplifier or similar circuit. Adjusting the gain is one way to control the loudness of the sound from a sound card.

gambling a popular, but often illegal, online form of recreation. Internet casinos are World Wide Web sites that offer games of chance, with the ability to place bets and receive money. Users are often under the impression that this activity is beyond the reach of local laws, but actually, gambling laws do not make any exemption for computers. U.S. federal law specifically prohibits placing bets “by wire” unless the gambling is legal at the locations of both parties.

A further difficulty is that there is no way for the casino operator to tell whether the players are human beings. Some of them could be computer programs, simulating the behavior of a human being at a web browser, and meanwhile collecting detailed information about the workings of the casino—the ultimate card sharp, so to speak. The feasibility of doing this has been demonstrated by Paul Apostolik at The University of Georgia, although, for legal reasons, no actual money was wagered.

See COMPUTER LAW.

Usage note: In the computer world, gaming does not mean gambling. It means playing computer games for recreation.

gamer a devoted fan of computer games. Gamers and the software they love best are responsible for pushing the limits of computer hardware further than most other groups.

gaming cafe a small business resembling an INTERNET CAFE but with an emphasis on computer games. Games are often networked and visitors can play against each other.

gamma (γ)

1. in computer graphics, a measure of the nonlinear response of a video screen. The brightness of a pixel on the screen is not proportional to the brightness value sent to it from software. Instead, the actual brightness B is

B = aV γ

where a is a constant, V is the brightness value, and the exponent γ is usually about 2 to 2.5. If gamma is known, it can be corrected so that all parts of the image are displayed with the specified brightness.

gamma testing

212

2. in photography, a measure of contrast. Normally, the gamma of film is about 0.7 and the gamma of photographic paper is about 1.4. When multiplied together, the two give a gamma of 1 so that the picture has the same contrast as the original subject.

gamma testing a third stage of software testing sometimes performed after beta testing but before commercial release. In gamma testing, the software is believed to be complete and free of errors, but the manuals and packaging may not yet be in final form. See also ALPHA TESTING and BETA TESTING.

gamut

1.in music, the range of notes in the scale.

2.the range of colors that can be reproduced by a screen, printer, or other device.

There is no way to reproduce all visible colors with a finite number of inks or phosphors. Properly mixed primary colors will give all hues, but not all at high saturation. A color is “out of gamut” if it is more saturated (brilliant) than the available inks can reproduce.

The gamut of an RGB computer monitor is very different from that of a CMYK printer (see CMYK). Vivid reds and blues on the screen are often unprintable with cyan, magenta, and yellow ink; other purples and rubyreds are printable but not displayable on the screen.

See COLOR and cross-references there. See also HSB; CMYK.

Gantt chart a diagram that shows the schedule for a series of tasks. See example at PROJECT MANAGEMENT.

garbage collection clearing out objects that are taking up space in memory but are no longer in use by a program. In Lisp, Prolog, Java, and C#, garbage collection happens automatically. In C++, there is no garbage collection; the programmer must specifically release the memory taken up by an object when it is no longer needed.

gas plasma display a computer display that works on the same principle as a neon light; the display is usually orange on black. Gas plasma screens were used on early laptop computers. They are bright and easy to read, but they consume considerably more electricity than LCD displays. A plasma is a glowing, ionized gas.

gate

1. one of the three parts of a field-effect transistor. See FIELD-EFFECT TRANSISTOR.

2. any of several logic circuits. See AND GATE; LOGIC CIRCUITS; NAND GATE; NOR GATE; NOT GATE; OR GATE.

gateway a link between different computer networks.

GB see GIGABYTE.

GC see GARBAGE COLLECTION.

213

gigabyte

gcc see CC.

geek (slang) an enthusiastic computer specialist; a person with an intense interest in computers to the exclusion of other human activities. The term is not normally an insult. Compare NERD.

gelatin silver print a conventional black-and-white photograph. (Black- and-white photographic paper uses a gelatin emulsion containing silver compounds that need not be replaced with colored dyes, though they can be.) Contrast CHROMOGENIC PRINT; GICLÉE PRINT.

Genuine Advantage a Microsoft anti-piracy program requiring users to validate their software. A key for the copy of the software is matched with a key for the hardware in an online database to prevent that copy from being used on other computers. The system will let people know if they have unknowingly bought counterfeit software, but a validation failure due to a network outage disables genuine copies of the software.

gibi- proposed metric prefix meaning ×1,073,741,824 (230), the binary counterpart of giga-. See METRIC PREFIXES.

gibibyte 1,073,741,824 bytes.

giclée print a picture printed on an inkjet printer, usually on coated paper to resemble a photograph. (In French, giclée means “sprayed.”) Contrast

CHROMOGENIC PRINT; GELATIN SILVER PRINT.

GIF (Graphics Interchange Format) a file format developed by CompuServe for storing bitmap images on disk. (See BITMAP.) GIF images can have up to 65,536 × 65,536 pixels and 256 colors. GIF is a common format for images on the World Wide Web. Compare JPEG; TIFF.

gif89a a GIF with the ability to play a short animation. They are very popular on web pages because, unlike FLASH, gif89a’s don’t require a plugin for the animation to play. Many programs can save a series of drawings to be an animated gif. One such is Adobe’s Image Ready.

You can have too much of a good thing, however. Esthetically speaking, a web page with too many animated gifs is confusing and way too busy.

giga- metric prefix meaning ×1,000,000,000 (109) or, in rating computer memories and disks, ×1,073,741,824 (= 10243). Giga- is derived from the Greek word for “giant.” See METRIC PREFIXES.

Gigabit Ethernet see 1000BASE-T; ETHERNET.

gigabyte (GB) approximately one billion bytes. With computer memories, one gigabyte is always 230 = 1,073,741,824 bytes = 1024 megabytes. With disk drives, a gigabyte is sometimes understood as 1000 megabytes. See also MEGABYTE.

FREE SOFTWARE; EMACS.

gigahertz

214

gigahertz (GHz) one billion cycles per second, a unit of frequency equal to 1000 megahertz; a measure of the frequency of a radio signal or the clock speed of a computer. See CLOCK; HERTZ; MEGAHERTZ; MICROPROCESSOR; RF; WIRELESS COMMUNICATION.

GIMP (Gnu Image Manipulation Program) a freely distributed paint program for UNIX and Windows, distributed from www.gimp.org. See also GNU.

Glide a service providing online software allowing users to access their data from any machine (web address: www.transmediacorp.com).

glitch erroneous response that occurs inside a computer because signals that are supposed to be simultaneous actually arrive at slightly different times. Software errors are occasionally called glitches. See BUG.

G.lite a popular, inexpensive type of ADSL telephone-line Internet connection that provides data rates up to 1.5 Mbps downstream and 0.5 Mbps upstream. See ADSL; DSL; and cross-references there. The name is a nickname for the standard’s official designation, G.992.2.

Global Positioning System see GPS.

global variable a variable that can be recognized anywhere in a program.

Contrast LOCAL VARIABLE.

glue logic additional, relatively simple logic circuits needed to connect one major part of a computer to another. For example, many microprocessors require some glue logic between the CPU and the memory. See LOGIC CIRCUITS.

glyph any printable character; the printed appearance of a character.

Gmail a free e-mail service provided by Google, with a large amount of space for messages and the ability to search through past messages.

GNOME (GNU Network Object Model Environment; the g is usually pronounced, like “g’nome”) the most popular graphical desktop environment for Linux, based on the X WINDOW SYSTEM and similar in look and feel to Windows 95 and 2000. GNOME is part of the GNU project. See

GNU. Compare KDE.

GNU a project led by Richard Stallman of the Free Software Foundation. GNU stands for “Gnu is Not UNIX”; the g is usually pronounced, like “g’noo.” The GNU project’s original goal was to develop a freely distributed substitute for UNIX, but Linux (the leading free UNIX) evolved into a somewhat separate project. The most important GNU products are the Emacs editor and the GNU C Compiler.

GNU software is copyrighted and is distributed free subject to certain conditions (typically, you must distribute it complete and intact, with source code). This set of conditions is sometimes called “copyleft” (i.e., a copyright with the opposite of its usual function) and also applies to some other free software, such as Linux. See also

215

Google Desktop

GO TO, GOTO a statement in Fortran, BASIC, and other programming languages that transfers execution to another place in the program. For example, here is a BASIC program that prints “Hello” 1000 times:

10 LET X=0

20 PRINT HELLO

30 LET X=X+1

40 IF X<1000 THEN GO TO 20

Use of the GO TO statement has been strongly discouraged since the 1970s, when E. W. Dijkstra and others discovered that it was very errorprone. If a program contains GO TO statements, it’s hard to tell, by looking at it, exactly how it will work, because execution can jump from any point to any other point. Instead, statements such as FOR, WHILE, and REPEAT are much easier for the programmer to get correct. See STRUCTURED PROGRAMMING.

gold, golden

1.(describing a disk or CD) ready to be duplicated and sold to the public.

2.(describing a software product) in its original manufactured state; thus “Windows 2000 Gold” is Windows 2000 as supplied on CD-ROM, without any subsequent updates downloaded.

gooey pronunciation of GUI. See GRAPHICAL USER INTERFACE.

Google a popular web search service that has expanded into many other areas (web address: www.google.com). Other search engines preceded Google in sending software SPIDERs (or webcrawlers) to automatically look at the text of a web page, and then follow all the links on each page to find other pages. In this way the search engine could create an index to the web, allowing people to enter words and then find a list of web pages including those words. However, that list might be very long, and it might contain irrelevant results. One reason Google became popular is because it developed a system to rank pages, based on the number of other pages that link to them. Also, it attempts to determine the relevance of the text on a page to the user’s query, so that more relevant results will be placed near the top of the list. Another reason for Google’s success is its large investment in computer hardware so its searches operate with great speed.

Google raises revenue largely through advertising, and it has expanded into other services, such as shopping, e-mail, mapping, and digital imaging. In 2008, it settled a lawsuit with publishers and authors over a plan to scan and index the text of a large number of books from major libraries. (Author’s Guild v. Google).

The word Google is also now used as a verb. For example, “I’ll Google that” means “I’ll search for that on the Web.”

Google Desktop a program provided by Google that allows the user to easily search through files, and provides a sidebar where gadgets can be installed. See GADGETS.

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