DLRN Glossary
Side imagemap with two links.
'Net
(n.) Shorthand for "Internet."

analog
(adj.) See also "digital." Measured or expressed continuously, the way a watch with a sweep-second hand measures or expresses time. Vinyl records store analog recordings of music.

asynchronous
(adj.) See also "synchronous." Literally, "apart from time." Asynchronous communication technologies are effective even when speakers and listeners do not participate at the same time. Electronic mail and books are examples of asynchronous technologies; both allow the sender to deposit information into the future.

bandwidth
(n.) Originally, "bandwidth" referred to the capactiy of a transmission system, expressed as the amount of digital data that could be moved through it per unit time. Prefixed with "high-" or "low-," bandwidth now also describes a Ônet-based resource in terms of the demand its content or functionality places on the tranmission system: "high-bandwidth" applications like real-time video conferencing are data-intensive. Low-bandwidth" content like plain text puts less strain on the transmission capacity of a network connection.

banner advertising
(n.) Advertisements that display as banners at the top or bottom of a web page. Host companies that provide free web space, scripting or message boards to end users sometimes derive revenue by selling such advertising to third party clients. These clients pay for the exposure they get when users call on sites that use the free resources.

blocking software
(n.) Software that blocks browser or newsreader access to specified sites on the internet.

browser
(n.) A computer application that fetches Web pages from servers out on the Internet and displays them on the user's local machine. Text-based browsers, such as Lynx, support text display and hyperlinks only. Graphical browsers, such as Netscape, Internet Explorer, Cello and Mosaic, also support image displays. Browser functions may be enhanced by installing optional software components (see "plug-in") to support the display of other web elements including sound, animation, video and virtual reality. Modern browsers allow users to keep lists of web sites they want to revisit, integrate messaging technologies such as electronic mail and newsreaders, and include features for managing these functions.

bulletin board system (BBS)
(n.) A bulletin board system (BBS) is an electronic venue typically accessible via direct modem/dial-up connection, using relatively simple telecommunications software. Once admitted, the BBS user has access to file archives and messaging systems provided by the BBS. BBS communities are the oldest species of online community. They existed a decade or more before the Internet spread to become the vast, populist, global system we know today. Internet-based communities, particularly those that utilize the Web (see also "message board"), have largely displaced BBSs, but some still exist for special interest groups.

chat
(n.or v.) See also "text-based chat," "mIRC" and "iChat." As a noun: synchronous (real-time) communication over a computer network, involving at least two users. Text-based chat means that the users "talk" to each other by typing messages on their respective keyboards and monitor the flow of discussion as a scrolling dialog on the computer screen. As a verb: to participate in such communication.

cognitive load
(n.) A measure of how hard it is to make sense of a stimulus. Cognitive load refers to the aggregate demand that a stimulus places on the sense-making capacity of the human mind. The higher the cognitive load of the stimulus, the more of a challenge it is to master. As familiarity increases, the cognitive load of the stimulus decreases. For example, Web sites with clear and consistent navigation systems place a lighter cognitive load on users than do Web sites with confusing or inconsistent navigation systems.

dial-up
(adj.) Describes a network connection via modem and telephone line.

digital
(adj.) See also "analog." Measured or expressed at discrete intervals; sampled. Common digital watches, like the ones you might buy in a department store, express time in discrete intervals -- no more often than once every second or every tenth of a second. Compact discs (CDs) store digital music -- music that is sampled, or recorded at discrete intervals, more than 40 thousand times each second.

discussion group
(n.) An online community in which participants communicate through an exchange of messages that are open to all.

distributed learning
(n.) A student-centered approach to learning that incorporates the use of technology in the learning process and, according to Chris Dede, emphasizes four educational characteristics: 1. supports different learning styles by using mixed media; 2. builds on the learner's perspective through interactive educational experiences; 3. builds learning skills and social skills through collaboration among learners and with the community; 4. integrates the learning into daily life by doing authentic tasks.

distance education
(n.) Learning and teaching that occurs when the student and teacher are not necessarily in the same place and/or interacting at the same time.

distance medium
(n.) A means or method of communicating across distance. Distance media include broadcast television, radio, cable television, satellite transmission, the telephone, and the Internet.

download
(v. or n.) As a verb: to copy a file from a central storage place -- say, a host or server -- to a remote computer. As a noun: any file so copied. Downloading can also refer to the movement of components from a central machine to a peripheral device, as when we "download fonts to a printer."

email
(n.) shorthand for "electronic mail."

feedback loop
(n.) The path that carries information from the person who receives a communication back to the person who sent the communication.

firewall
(n.) A system for preventing unauthorized users from gaining access to a local network. Firewalls may use hardware, software, or a combination of both. There are three common firewall strategies: gateways restrict access to physical sections of the system or to particular software applications; proxy servers work by concealing the true network addresses of component machines; and packet filtering systems inspect every data packet entering or leaving the network, accepting or rejecting each on the basis of rules defined by the system administrator.

flame
(n. and v.) As a noun: a scorching rejoinder posted as email, overly harsh and frequently unfairly personal. As a verb: to post such a message.

graphic design
(n.) The branch of visual arts concerned with the aesthetics and production of layout, design and typography. In the context of Web resources, graphic designers are responsible for the look of a site and all its visual elements including page layout, background and spot imagery, color scheme, typography, navigation buttons, etc.

host
(n. and v.) As a noun, a host is the same as a server; that is, the word "host" refers to the computer in a network where (for example) web sites reside, or where the software that supports delivery of services like chat, email, listserv, etc. is installed. As a verb, the term "to host" is synonymous with providing such services.

HTML
(n.) HyperText Mark-up Language can be thought of as the "code" in which Web pages are written. Technically, HTML is a "page definition language;" its elements (called "tags") are interpreted by browsing software as instructions for displaying or otherwise handling Web-page content.

hyperlink
(n. and v.) As a noun: graphics or text strings in web documents that respond to user selection by taking the user to a different location or presenting a different Web page or other resource. On Web pages, text links typically appear highlighted in an underlined font of some color that differs from the color of regular text. As a verb: to create a hyperlink; to make a hypertext connection with another page, passage or resource on the Web.

hypertext
(n.) Text that is (a) organized so that the reader has choices about the pathway of ideas s/he follows while reading, and (b) supported by a technology that makes it easy to "jump" or "link" to the next set of ideas along the chosen path.

iChat
(n.) See "text-based chat."

Instructional Design
(n.) The systematic process of creating or adapting instruction, including at least these steps: defining the problem or knowledge gap that the instruction is meant to address; defining the audience that the instruction is meant to serve; developing objectives and assessment strategies; selecting and sequencing content and learning activities; evaluating the instruction; revision.

interactive
(adj.) Describes a system that responds to user input -- i.e., that interacts with users.

interactivity
(n.) 1. The quality of being interactive. 2. A particular type of instructional resource involving information exchange or dialog via the online medium.

Internet
(n.) A globe-spanning network of networks, the Internet grew out of a national data transmission system originally implemented in the 1960s by the US Department of Defense. The original system was put in place to give government scientists scattered around the country access to powerful computers without building a lot of the expensive machines. TodayŐs Internet is a dense, redundant system made up of many autonomous parts managed locally by businesses, schools, governments, individuals and organizations. It utilizes the telephone wires, fiber optic links, infrared and satellite transmission and other telecommunications technologies to support the transmission of digitized signals.

Internet telephony
(n.) Systems consisting of hardware and software that enable users to make telephone calls over the Internet.

JavaScript
(n.) A web scripting language developed by Netscape. JavaScript shares selected attributes and data structures with the Java programming language, but it was developed separately and it is not Java. JavaScript works within an HTML page, and is supported by Netscape versions 3.0 and higher. A subset of JavaScript, called JScript, is supported by the Microsoft browser, Internet Explorer.

JavaScript-enabled
(adj.) Describes a browser that can support JavaScript, and is configured to do so under User Preferences or Options.

kill file
(n.) A list of email addresses from which you, the user, do not wish to receive postings. The kill file is used by the bozo filter in your email or newsreader software to screen incoming messages and reject those you do not wish to receive.

link
(n. and v.) See "hyperlink."

link rot
(n.) A colloquial expression referring to the tendency of hyperlinks to "decay" as their destination sites are purged from their host servers. Users experience "link rot" as hyperlinks that lead nowhere, or that prompt "Error 404: file not found" messages.

listserv
(n.) See also "majordomo." A commercial electronic mailing list server application, developed in 1986 and marketed by L-Soft International. The word "listserv" is sometimes (incorrectly) used to refer to the general category of electronic mailing list management application software.

majordomo
(n.) A freeware automatic electronic mailing list server application. Mailing list servers automate the distribution of electronic mail to large groups of subscribers. The server automates the subscription process, by which users join a list to receive its postings. The server also forwards to all subscribers all messages sent to the list. Subscribers may also send commands to the list to retrieve specified text files stored in its archives.

message board
(n.) A web-based message center, where users may post text communication for one another. Messages so posted are converted into Web documents, and may be viewed with browsing software. Message boards differ from email the way a bulletin board at the supermarket differs from the postal service: in their most basic form, message boards must be visited to be read. However, some message boards do offer enhanced services to users, including the option of receiving email notification of new postings, or even email forwarding of the posted messages themselves. Web Crossing is an example of an enhanced message board system.

messaging
(gerund) A generic term encompassing several modes and methods of online communication between people (as opposed to machines). asynchronous messaging technologies include electronic mail, newsgroup postings, and message boards. Synchronous messaging technologies include chat and internet telephony.

mIRC
(n.) See "text-based chat."

modem
(n.) A device that connects a computer to the telephone network. The word "modem" comes from the phrase "MOdulate-DEModulate" and refers to the way the device manipulates an electrical signal in order to encode information for transmission via the telephone network.

MOO
(n.) See also "MUD." Acronym for "MUD, Object Oriented." MOO is a particular implementation of a MUD system created by Steven White that features a sophisticated programming language that enables users to construct "worlds" within the enviornment. It's freeware.

MUD
(n.) See also "MUSE." Acronym for Multi-User Domain. A MUD is an electronic venue where users can adopt an identity (called an "avatar") and interact with each other in real time. MUDs have their origin in fantasy and role-playing games, but today MUDs exist for a variety of purposes, including education. Find out more at Jennifer Smith's FAQ: Basic Information About MUDs and MUDing.

MUSE
(n.) See also MUD. Acronym for Multi User Simulated Environments. Another specific implementation of a MUD system, hosted at BBN/GTE Internetworking, MUSEs support multiple participants collaborating in real time to construct a virtual world.

b>Net
(n.) Shorthand for Internet.

online
(adj.) Strictly speaking, "online" implies a live connection to the Internet. The word is also used more casually to describe content and applications that are accessible via the Net.

platform-independent
(adj.) Describes software or other technology that "doesn't care" what kind of computer the end user has. Platform-independent applications may run on any kind of computer (example: programs written in the JAVA programming language), or may not rely on the end user's system for anything other than display and input (example: HTML pages on the Web).

plug-in
(n.) A software module that adds enhanced display or rendering capabilities to your browser software. Plug-ins enable you to view, hear, or interact with non-standard display formats, including those for video, audio, multimedia, and VR.

real-time
(adj.) See "synchronous."

remote
(adj.) Distant, residing on a network node or computer other than the user's own.

search engine
(n.) A search engine is a web-based software tool that enables the user to locate sites and pages on the web based on the information they contain. Hierarchical search engines organize known sites in "trees" that the user browses in order to find a site that deals with a particular topic. Yahoo (http://yahoo.com) is an example of hierarchical search engine. Free-form search engines typically present a form in which the user types words that specify the information sought. The search engine returns a hot list of pages containing those words. AltaVista (http://altavista.digital.com) and Excite! (http://www.excite.com) are examples of free-form search engines.

server
(n.) See host.

set-top box
(n.) A device that connects your television set to the Internet, either by telephone line or cable modem. More information: Ruel's Set-Top Net Page.

Shockwave (R)
(n.) A trademark of Macromedia Inc., for a platform-independent technology it developed that allows Web pages to include multimedia (developed using Macromedia Director). Shockwave requires the user to install a plug-in.

slow connection
(n.) Access to the internet that is characterized by low rates of data transmission. Once, a slow connection passed no more than about 25 characters per second (300 baud). Today, transmission rates of more than a megabyte per second are possible, so that a "slow" connection may be as "fast" as 28.8 kilobytes. The lower (or slower) the transmission rate, the more time it takes for the data (such as a web page) to download to the end user. Designers of online instruction need to take end-user connections into account when constructing resource components.

surfing
(gerund) "To surf" the Web is to browse around, with or (usually) without a clear objective. "Surfing" the web suggests a shallow information-foraging behavior or a recreational experience.

synchronous
(adj.) See also "asynchronous." Coinciding in time. (Also called "real-time".Synchronous communication technologies require the simultaneous participation of the communicating parties. Internet Chat and the bullhorn are two examples of synchronous communication technologies. Neither is very effective if no listeners are present at the moment that the speaker holds forth.

T1
(n.) A dedicated connection to the Internet, also known as DS1, that uses telephone lines and can support a data transfer rate totaling 1.54 megabytes per second by sending data across 24 discrete channels at 64 kilobytes per second. Individual users may purchase access via all 24 channels, or just some subset; this is called "fractional T1" access.

telementoring
(n.) The use of telecommunications technology, including the Internet, to support mentoring relationships.

text-based chat
(n.) See also "mIRC" and "iChat." See "chat," above

thematic units
(n.) Instruction that integrates multiple disciplines and subject areas around a common theme. A thematic unit on seabird migration, for example, might integrate language arts, zoology, meteorology, geography, mathematics, and environmental science.

threaded discussion
(n.) A threaded discussion is an online dialog or conversation that takes the form of a series of linked messages. The series is created over time as users read and reply to existing messages. Typically, messages in a given thread share a common subject line and are linked to each other in the order of their creation. Threaded discussion is particularly useful in online venues where multiple discussions unfold at the same time. Without threaded discussion, the reader would confront a chaotic, unsorted list of messages on many different topics. By hyperlinking messages that share a common subject line, threaded discussion makes it easy for the reader to focus on one conversation and avoid the distractions of unrelated postings.

URL
(n.) Acronym for Universal Resource Locator. The Internet address of a specific resource. All URLs have at least two components: one part identifies the host computer on which the resource resides, and another part identifies the destination that is the resource itself. An email address is an example of a URL that includes only those two parts. But most URLs also include a third component -- namely, the path of directories and subdirectories that must be traversed on the host computer to locate a destination file. Web page addresses are almost always URLs of this more complex variety.

virtual reality
(n.) Artificial, computer-based environments in which users can have experiences that look and feel "real," or at least plausible. The most elaborate VR environments completely immerse the user in an artificial world, but today require expensive hardware and software. Less elaborate VR experiences may be offered over the Web to provide different perspectives on systems and phenomena that aren't readily accessible in other ways.

virus
(n.) A computer virus is a roguish snippet of software code that (1) rides around a network attached to "legitimate" software or document templates, and (2) can do at least two things. First, it can make copies of itself and so propagate to other machines and systems it encounters. Second, when it arrives at a target machine or system, it can make things happen there without the local operator's awareness or consent. Some viruses are merely impish, displaying, for example, cryptic phrases or dirty words on the target's monitor. But others are destructive, altering or obliterating critical data and even rendering the target system inoperative.

Web
(n.) See World Wide Web. Short for "World Wide Web." The Web is a global, networked system of dedicated host computers that serve documents (files) formatted in HTML (see "HTML"). These documents (or "web pages") can contain text, images and multimedia components, can include hyperlinks (see "hyperlinks") to other such documents on different servers, and can also act as interfaces, linking users with underlying special-function applications. The Web debuted in 1993, and its inception is commonly credited to Tim Berners-Lee of CERN in Switzerland. It was originally conceived as a platform-independent tool that scientists could use to exchange documents about their work. Many people incorrectly equate the Web with the Internet. The Web utilizes the Internet as its transmission medium; they are not the same thing.

Web page
(n.) A Web page is a document, the basic data storage and display unit of the World Wide Web. Stored as plain ASCII text, a web page embeds "tags" or function and formatting codes which govern its transmission and display on the end-user's computer screen. These tags are standardized as HTML, the hypertext markup language.

Web site
(n.) An electronic venue consisting of a collection of thematically related and hyperlinked documents (called "web pages") and their component images, multimedia objects, etc. Web sites are identified by their addresses, called URLs. (see "URL")

World Wide Web
(n.) Also known as the Web. One of many schemes for serving data via the Internet, the Web was created in the early 1990s by CERN in Switzerland to provide physicists around the world with rapid, easy access to each otherŐs written work, even though they all used different kinds of computers to create their reports. Invented by Tim Berners-Lee as a document serving and display system, todayŐs Web can serve and display virtually any sort of digitized data including images, motion video, music and speech. Other recent advances in Web-based programming allow users to manipulate their own data using either remote computing resources or applications that reside online and download to the userŐs computer when needed.




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