Glossary

archival: Archival publications are those designed to preserve and store the information they contain for future use, as well as to distribute the information to subscribers at the time of publication. To merit the storage and maintenance of such publications for long times in archives such as libraries, contributions usually are reviewed before publication by peers of the authors to determine whether or not the contributions seem appropriate to distribute and to archive.

ASCII: American Standard Code for Information Interchange, represents a set of standard text characters as 8-bit binary numbers. The set of 256 characters includes lower case and capital Latin letters, the digits from 0 to 9, standard punctuation marks and several special characters. ASCII text is supported by essentially all contemporary computers and hence serves as a bare-bones (no text formatting) common language for communicating between computers with different operating systems. For example, typical Windows, Macintosh and UNIX computers all have software for producing and displaying ASCII text files.

browser: software designed to display files available on the World Wide Web. Browsers typically handle HTML and multimedia files, but can be configured to accept, in addition, more specialized file types. Although initially designed to display files on the World Wide Web, browsers can display files that reside on locals disk drives, as well.

CD-ROM: Compact Disk - Read Only Memory, a widely used means of accurately and inexpensively storing digital data for distribution and subsequent use. Initially, CD-ROMs were used mainly for distribution of digitally recorded music. Later, they proved useful for distributing software, multimedia and other digital data specifically intended for use with computers.

FTP: File Transfer Protocol, the process by which files can be transferred between computers on the Internet. Most browsers permit files to be downloaded from an FTP server on the Internet to a local disk drive. Uploading a file to an FTP server from a local disk drive usually requires additional software.

GUI: Graphical User Interface, a view of computing resources in which various kinds of files, including software, are represented by small pictures, or icons. Manipulation of the files is achieved by manipulation of the icons with a mouse. Command line interfaces to computing resources, in contrast, present the user with a symbolic prompt when the computer is ready to accept typed commands. A major difficulty with command line interfaces is that users are required to remember what commands are acceptable in a particular context. The icons in a GUI, on the other hand, suggest to users what the computer is ready to do. Not only do GUIs permit users to rely less on their memories, GUIs demand less advance knowledge of what is possible in a given context and thus encourage interactive exploration of the available resources.

HTML: HyperText Markup Language, a language for writing documents that appear on the World Wide Web. HTML documents are stored as ASCII text files. Special features of the document are indicated by HTML tags, which consist of <text within brackets>. To make a portion of text appear in bold face type, for example, the HTML tag <B> must appear just before that portion begins and the tag </B> must appear just after it ends.

HTTP: HyperText Transfer Protocol, the set of rules for communication between WWW servers and WWW browsers.

hyperlink: originally a contraction of the term hypertext link, a construct that makes it possible to jump from one place in a text document to another. Subsequently, the term hyperlink has come to include hypermedia links to multimedia resources, as well as links to text. In an HTML document, a hyperlink can be represented by underlined text of a different color. Clicking on this hyperlink, for example, takes you to the URL entry in this glossary, where you will find a hyperlink to the IEEE home page on the WWW. Usually, the term hyperlink is contracted further simply to the term link.

relative addressing: In an HTML document, the opposite to absolute addressing of files on a local disk, such as a CD-ROM. Suppose, for example, that a table of contents HTML document of a CD-ROM lies in a subdirectory /CONTENTS/ of the root directory and that a link in the table of contents document is to refer to a file, INDEX.HTM, in the subdirectory /099/CDROM/. Using absolute addressing in the table of contents document, we would refer to the file as FILE:///099/CDROM/INDEX.HTM. Using relative addressing, however, we would refer to the file as ../099/CDROM/INDEX.HTM. The characters ../ move focus up one level of the directory structure, out of the subdirectory /CONTENTS/, into the root directory of the CD-ROM. From there, the remainder of the address, CDROM/INDEX.HTM, leads to the file. With relative addressing, therefore, all movement through files is relative to an entry point in the CD-ROM structure. The root directory is never referred to explicitly. Using relative addressing in HTML documents on a CD-ROM thus circumvents the problem that different operating systems refer to the root directory in different ways and hence require different path formats for absolute addressing. Relative addressing hence should be used in all HTML documents on a CD-ROM intended for use on multiple computer platforms.

server: a computer placed on a network to provide files and services to other computers on the network.

URL: Universal Resource Locator, the address of a resource, sometimes called a site, on the Internet. All URLs for WWW sites begin with the prefix http://. The URL for the IEEE home page on the WWW, for example, is http://www.ieee.org. All URLs for FTP sites begin with the prefix ftp://. URLs for files on local disk drives use the prefix file://.

WWW: World Wide Web, a visual and aural perspective of the Internet. Often, the WWW is shortened to simply "the Web."