Glossary

© 1997 by Prentice Hall PTR


A general and more extensive list of terms is available from

· Free Online Dictionary of Computing

http://wfn-shop.Princeton.EDU/foldoc/ (US)

http://wombat.doc.ic.ac.uk/ (Europe)

· Dictionary of Dictionaries

http://www.refdesk.com/facts.html#dict

· The Cook Report - An Internet Monthly

http://pobox.com/cook/glossary.html

Note: The definitions here relate to how the terms are used in this book and may differ slightly from the definitions used by others.

101 A basic introduction to a topic.

Anonymous ftp A mechanism to get files from, or put files to, a remote computer, when you do not have an account on that remote computer.

Applet Code written in the Java language that is downloaded to the client via a Web browser and executed. Frequently used to support animation and continuous client server interaction.

ASCII American Standard Code for Information Interchange. A set of 8-bit binary numbers representing the alphabet, punctuation, numerals, and other characters used in text representation.

Bit-mapped Display A display that supports addressing of pixels (points on the screen) rather than specific characters on a line of length 80 or 132 characters.

Byte Code Machine independent code generated by the Java compiler.

CERT Computer Emergency Response Team. A government funded group which, among other things, produces bulletins of known security problems on the more popular operating systems and issues patches (fixes) from the vendors and others. See ftp://info.cert.org/pub/ for further details.

CGI Common Gateway Interface. A means of passing information from a Web client browser to a CGI-compliant script resident on a Web server. The CGI script will invoke some action, like the generation of HTML pages, that are sent back to the client browser.

CGI program Used interchangeably with CGI Script. Strictly speaking, a CGI script uses an interpretive language and a CGI program uses a compiled program.

CGI Script A file containing an executable program, code interpreted by an interpretable language, (e.g., Tcl, Perl) or code interpreted by the UNIX shell, which is invoked by the Web client and executed on the Web server.

Clickable Map An image that has a series of URLs mapped to different regions of the drawing, thereby providing visual navigation.

Common Gateway Interface See CGI.

Common Log File Format The de facto log file format produced by popular Web servers when logging access to the server.

Daemon A program important to the functioning of a UNIX system. Rather than being part of the kernel, daemons run as standalone programs, usually started at boot time. Daemon, not to be confused with demon, is taken from the Greek meaning something, neither good nor evil, that helps define personality and character.

Document Root Directory The top level directory recognized by the Web server that contains documents to be served. All documents served are found in this directory or below it in the directory tree. Symbolic links to files being served outside of this tree may be allowed. Support for symbolic links is Web server dependent.

FAQ Frequently Asked Questions. A useful means of quickly asking the most obvious questions on a particular subject by way of a Listserver.

File Extension Any characters following (and including) the last period in a UNIX file name.

Filter Software that converts information in one format to the same information in another format.

Ftp File transfer protocol. Part of the TCP/IP stack of protocols controlling file transfer between two computers.

Ftp Archive Files accessible by anonymous ftp, hopefully organized in a way to make it easy for the user to find the information they need.

GIF Graphics Interchange Format, developed by CompuServe. A popular and free graphics format supported by Internet information servers.

Gopher Text-based predecessor to the Web. Used a different protocol to http, but supported the idea of hyperlinks.

GUI A Graphical User Interface (GUI) is the hardware and software needed to address (by way of a mouse or some other pointing device) an individual point on the display device and solicit a particular response.

Helper Applications Applications configured and subsequently invoked from a Web browser to process a MIME type not recognized by the browser itself.

Hit A single access to an information server. For example: the downloading of a single Web page or graphic image from a Web server; a single mail message sent to a Listserver; a single file transfer using ftp. The number of hits is an approximate measure of the amount of activity on a server.

Home Page A particular Web page. A point in the World Wide Web that represents the starting point for viewing a specific body of information.

HotJava A Web browser written in the Java programming Language, developed by Sun Microsystems Inc.

Hot List A list of URLs to which the user refers frequently and which are maintained by the client Web browser.

http HyperText Transfer Protocol, the protocol used by the World Wide Web.

Hyperlink (or Hypertext Link) A virtual connection between two pieces of information accessible via the Internet.

HyperText Markup Language (HTML) "The language of the Web" used to define Web pages.

IP Address A number and associated name by which Internet hosts are recognized.

Internet Conglomeration of interconnected computer networks all using the TCP/IP protocol.

Intranet Conglomeration of interconnected computer networks within a specific organization.

ISDN Integrated Services Digital Network, a fast network connection available through many telecommunications companies.

Internet Service Provider (ISP) A commercial organization that provides Internet access to commercial and private users.

Java Object-oriented programming language designed by Sun Microsystems Inc., with network access and portability in mind.

JavaScript Simplified version of Java designed by Netscape Communications Inc., for use with Netscape Web browsers and Web servers.

Just-in-Time Compiler A compiler that takes Java byte code and converts it to more efficient machine-specific code. This is done at run-time.

LaTeX Word processing system derived from TeX.

Line Interface An interaction with the computer on a line-by-line basis. You enter a text string followed by <enter>. The <enter> signifies that the computer should process the line(s) and produce a response. Contrast this to a GUI. All display devices support a line interface.

Link See hyperlink.

Listserver Software that serves lists of users. A user subscribes to the list and thereafter any e-mail postings sent to the list are forwarded to the user. This continues until the user unsubscribes from the list.

Markup The act of adding information to a document to control how it will be formatted for a printer or display device.

Methods Also called procedures. A term loosely taken from object-oriented programming and meant to imply a piece of reusable code for performing a specific task.

MIME Type Multipurpose Internet Mail Extension is a standardized method of assigning types to documents. It was originally developed for use with mail messages. That is, mailers could recognize specific types of documents embedded in mail messages by their MIME types. This same mechanism has now been adopted as the mechanism for assigning and detecting the formats of Internet documents.

Mirror Site An information server that keeps a current copy of all or part of the information found on another information server. The prime purpose of a mirror site is to make the same information easily accessible from different global locations, thereby avoiding slow Internet connections.

Moderated List A list available on a Listserver, where each incoming message to that list is examined by the person referred to as the List Moderator, before being optionally broadcast to all subscribers to that list after possible modification.

Netiquette Undefined rules for how to behave when accessing the Internet. Common sense on the Internet.

NNTP Network News Transport Protocol, the protocol used to access Usenet newsgroups and associated articles.

PC Personal Computer. Any computer using the Intel 386, 486, Pentium or other Intel chip.

Plug-in A Netscape term for an application that "plugs-in" to the Netscape browser and extends the capabilities of the browser. Refer to http://home.netscape.com/eng/mozilla/2.0/-handbook/docs/appans.html#C13 for details.

PPP Point to Point Protocol, another protocol with similar functionality to SLIP.

Procedures See Methods.

README The name of a file commonly found in ftp archives and software distributions. Usually contains information important to the installation or information that was written too late to be placed in the formal documentation.

Rich Text Format (RTF) ASCII-based text interchange format developed by Microsoft Inc. Works well for exchanging text between word processing systems that read and write RTF, but is not so good for exchanging graphics and mathematical equations.

Robot See Web Robot.

SLIP Simple Line Interface Protocol, a protocol used to support asynchronous connections to the Internet, typically over telephone lines.

SHTP Secure Hypertext Transport Protocol, extension to e-mail that provides privacy and authentication over the World Wide Web.

SGML Standard Generalized Markup Language, used by the publishing industry to describe the final appearance of a document. HTML is a subset of SGML.

SMTP Simple Mail Transport Protocol, the e-mail protocol used on the Internet.

Style Guide A reference document and possibly software templates that define common characteristics to be used in developing Web pages.

Swapping The moving of pages (i.e., 512 byte chunks of information) between physical memory and disk.

TCP/IP Transmission Control Protocol/Internet Protocol. The protocol suite that allows communication on the Internet. That is, all computers connected to the Internet support this protocol.

TCP/IP Protocol Stack The specific protocols included in TCP/IP.

URL Uniform Resource Locator. A global reference point to a piece of information. That information can exist in a variety of formats. All Web browsers recognize and display the contents of URLs.

Usenet Newsgroups Discussion groups on the Internet, each centered around a specific topic. There are currently about 15,000 Usenet newsgroups. Users post messages by e-mail to newsgroups and review newsgroups either via e-mail of special newsreader software.

Virtual Reality Modeling Language (VRML) Can be thought of as a 3-D version of HTML. VRML defines behaviors through which the user navigates using a VRML browser.

Web See World Wide Web.

Web Browser Client software capable of reading, interpreting, and displaying information in HyperText Markup Language (HTML).

Web Client Software resident on client hardware for interpreting Web pages downloaded from a Web server.

Web Form A particular type of Web page for sending information to the Web server for processing.

Webmaster The generic name given to the person responsible for maintaining Web pages on a Web server.

Web Page A discrete piece of information read by a Web browser. That information resides between <HTML> and </HTML> tags and is usually contained in a single file.

Web Robot Software that moves around the Internet gathering and indexing Web pages. Most commonly used to support Internet search services like Yahoo, Alta Vista, and Magellan.

Web Server Computer running software (or the software itself) capable of serving requests from Web clients for documents in HTML format.

Web Site Computer maintaining a set of Web pages with a related theme.

WYSIWYG What-You-See-Is-What-You-Get. Usually refers to an editor that allows you to work with the document in the form it will appear on the printed page.

World Wide Web Computers attached to the Internet that support the http protocol used in global information exchange.

WWW An acronym for World Wide Web.