A Teacher's Guide to Distance Learning

Glossary

56Kbps data line
A special telephone line that is designed to transmit computer data at 56Kbps. It will probably be replaced by ISDN lines over the next few years.
Acceptable use policy (AUP)
A policy that restricts the use to which a computer network may be put. For example, some networks do not allow commercial use.
Analog
Information stored as an electrical signal with a continuous scale. Videotape and audiotape are analog.
Asynchronous
Communications between the student and teacher that do not take place simultaneously.
Audio bridge
A method used to connect multiple telephone lines for an audioconference.
Audioconferencing
Voice-only communications linking two or more sites. In most cases, standard telephone lines and speakerphones are employed.
Audiographic conferencing
Voice communications supplemented with the transmission of still images. Pictures, graphs, or sketches can be transmitted during the conference. Standard facsimile (fax) machines are used, or computer-driven systems can be used.
Bandwidth
The transmission capacity of a telecommunications system. The greater the bandwidth, the greater the amount of digital information that can be transmitted per second.
Baud rate
How many bits a modem can send or receive per second. Derived from the name of Emil Baudot, a nineteenth-century inventor.
Bulletin board
A computer-based meeting place (and its accompanying software) that allows people to discuss topics of interest, upload and download files, and make announcements.
Bits-per-second (bps)
A measure for bandwidth or speed of modem transmission. Common rates are 2400, 9600, 14,400 and 28,800.
Bookmarks
A list of sites that can be saved by browser software. The hotlist enables user to access favorite sites without retyping the URL.
Bridge
A device, often leased through a telephone company, that links three or more telephone lines together for audio teleconferencing. See call-in bridge and call-out bridge.
Browser
A software program used to look at various Internet resources. Browsers are either text- or graphics-based.
Byte
A set of bits that represents a single character. Usually there are eight bits in a byte.
Call-in bridge
A telephone bridge where the conference is established by having all of the distant sites call in to the bridge telephone number. Long-distance charges are billed to the distant locations.
Call-out bridge
A telephone bridge where one location calls all distant sites to connect each site to the teleconference. Any long-distance charges are billed to the one originating location.
Capture
Saving a file to your computer from a remote system. Capturing data, or saving to disk, allows the user to view or print online data at a later time.
CD-ROM
A small optical disc that can store over 650 MB of digital data.
Chat mode
Synchronous exchange of text through the Internet.
Client
A software program used to contact and obtain data from a server program on another computer; a computer running this software.
Closed circuit television
A point-to-point television distribution system installed on a wire-based system. Used in many schools.
Codec (COmpression-DECompression)
An electronic device that converts standard television signals into compressed digital signals for transmission. The same device can convert incoming compressed digital signals back into viewable television signals. A codec allows motion images to be transmitted through special telephone lines.
Commercial Online Service Provider
A company that provides various online services through a service agreement with the user. Examples are America Online, CompuServe, and Prodigy. Most of these services also provide access to the Internet.
Compressed file
A computer file that has been reduced in size through a compression program, such as PKZIP. The user must decompress these files before using.
Compression
Digital signal-processing techniques that are used to reduce the amount of information in a video signal. This allows the video signal to be sent through telephone data lines.
Connect time
The length of time a user is connected to an online service, such as CompuServe or America Online.
Database
A collection of information, usually organized with searchable elements, or fields. For example, a library catalog may be searched by author, title, or subject.
Dedicated telephone line
A permanent telephone connection between computers. Usually a regular phone line that is not used for anything but data transmission.
Desktop videoconference
Multimedia microcomputers are used to display live video images that are transmitted over LANs or digital data lines.
Dial-up connection
A temporary, as opposed to dedicated, connection between machines established over a standard phone line.
Digital
Information that is stored in bits and bytes. Computer data is digital.
Digital data line
A telephone line that is designed to transmit computer data rather than human voices. See 56Kbps data line, ISDN, T1 line, and T3 line.
Downlink
A location that receives a video teleconference from a satellite.
Download
To transfer a file from a remote computer to your own.
Duplex
A process that allows information to flow in both directions at once, like a standard telephone conversation. Contrasts with simplex.
DVD
An optical storage device, often used for storing video (such as movies). DVD is commonly known as Digital Video Disc -- it has a capacity of several gigabytes of data.
E-mail
Electronic mail; messages that are sent via a computer network, i.e., electronically. The messages are stored until the addressee accesses the system and retrieves the message.
Fax (facsimile machine)
An electronic device that transmits text or graphics material over telephone lines to other locations.
FAQ (Frequently Asked Questions)
Files maintained at many Internet sites, especially newsgroups, that provide answers to common problems. Intended to bring novices up to speed without posting repetitive questions.
Fiber optic
Network cable made from glass. Transmits data at extremely fast rates.
FTP (File Transfer Protocol)
An application used to transfer files between your computer and another on the Internet. FTP is a special way to login to another Internet site to retrieve and/or send files. Many Internet sites have established publicly accessible material that can be obtained through FTP; the user logs in using the account name anonymous. These sites are called anonymous FTP servers.
GIF (Graphic Interchange Format)
A widely used format for image files.
Graphical user interface (GUI) browsers
Mouse/icon-oriented software used to search the Web. GUI browsers automatically display the graphics embedded in Web pages and usually can be configured to access multimedia features, such as sound. Mosaic and Netscape are two very popular GUI browsers.
Graphics tablet
A computer device that converts hand-drawn images into digital information that can be displayed on computer screens.
Home page
The introductory page to a Web site.
HTML (HyperText Markup Language)
Coding language used to create hypertext documents to be posted on the Web. HTML code consists of embedded tags that specify how a block of text should appear, or that specify how the word is linked to another file on the Internet. HTML documents are viewed with a browser, such as Netscape.
HTML editor
A software program that helps to create documents in HTML by automatically embedding the code or tags.
HTTP (HyperText Transport Protocol)
The protocol for moving hypertext files across the Internet; the most important protocol used on the Web.
Hypermedia
A program that contains links to other media, such as audio, video, or graphics files.
Hypertext
Any text that contains links to other documents or files.
Internet
An Internet is a network. The term Internet is usually used to refer to a collection of networks interconnected with routers. What has been commonly called the Internet (with the capital I) is the largest Internet in the world.
ISDN (Integrated Services Digital Network)
A modern telephone system that allows rapid digital transmission of sound, data, and images.
ISP (Internet service provider)
A company or other group that provides access to the Internet through dial-up, SLIP/PPP, or direct connection.
ITFS (Instructional Television Fixed Service)
A set of microwave frequencies that have been designated for use by educational facilities. Allows line-of-sight television transmissions over ranges of about 20 miles.
JPEG (Joint Photographic Experts Group)
A common file format for images.
Ku-Band
Satellite transmissions that use a frequency band between 10.95 Ghz and 14.5 BHX. It is the frequency band used by new home systems.
LAN (local-area network)
A computer network limited to a building or area of a building.
Leased line
A phone line established for exclusive data connections from one location to another.
Listserv
A common type of automated mailing list distribution system, developed originally on BITNET, but now common on the Internet. Subscribers receive all messages posted to the list.
Microwave
A high-frequency transmission that can be used for television signals or computer data. Microwave transmissions are said to be line of sight, which means that they cannot pass through tall buildings or mountains.
Modem (MOdulator-DEModulator)
A device that enables a computer to transmit and receive data from another computer through a phone line by converting the data into sound.
MPEG (Motion Picture Experts Group)
A digital video file format.
Newsgroup
Discussion forum on the Internet.
Offline
Literally, not connected. Used to denote time spent preparing information to upload to a remote system, or to read information downloaded from a remote system.
Online
Communications via a modem or network to a host system; the time the user is actually logged into the host.
Packet
A chunk of data sent across a network; in packet switching the data being transmitted from one computer to another is broken into packets; each packet has the addresses of its origin and where it is going. These chunks mingle in the same lines and are directed and sorted along the way. This system allows more than one person on a line at the same time.
Parameters
Values that must be set in a telecommunications software program, including number of stop bits, start bits, and speed.
Podcast
A series of digital files (audio or video) that can be downloaded from the Internet. A user can subscribe to a series of podcasts and the new files will be downloaded automatically as they are posted.
PPP (Point-to-Point Protocol)
A protocol that provides a method for TCP/IP to run over a standard phone line. PPP is newer, and faster, than SLIP.
Protocol
A description of message formats and the rules computers must follow to exchange those messages.
Router
A computer or software package that handles the traffic between two or more networks.
Server
A computer, or software package, that provides a specific service for client software running on other computers. For example, a Web server provides clients access to the Web.
Shareware
Software made available free for a limited time. After a trial period, the user is asked to pay a fee to the developer.
Simplex
A communication process that allows information to flow in only one direction at a time. Common speakerphones are simplex devices because only one person can speak at a time. Contrasts with duplex.
SmartPhone
A cellphone that includes advanced digital data features, such as Web access, games, video, etc.
Synchronous
Communications between the student and teacher that take place simultaneously.
T1 line
A special type of telephone line that transmits digital information at a high rate. These lines are much more expensive than regular telephone lines.
T3 line
A telephone line that is capable of transmitting digital information at rates even higher than those of a T1 line.
TCP/IP (Transmission Control Protocol/Internet Protocol)
The language used by computers to transmit data on the Internet.
Telecommunications software
A program that allows a computer to communicate through a modem to another computer. Most telecommunications software can be configured so that dialing and setting of parameters are automatic.
Teleconferencing
Electronic techniques that are used to allow three or more people at two or more locations to communicate.
Terminal emulation
Telecommunications software allows a computer to appear to be an appropriate terminal, or work station, to a host.
Uplink
The site for a video conference from which a signal is sent to a satellite.
Upload
The process of sending a file from one computer to another.
URL (Uniform Resource Locator)
Addressing scheme used to identify Web sites.
Videoconferencing
Transmitting motion video and audio to two or more locations for the purpose of interactive conferencing.
Web (World Wide Web)
The network of hypertext servers which allows text, graphics, and sound files to be mixed together and accessed through hyperlinks.
WebQuest
A web-based activity in which learners read, analyze, and present information. WebQuests are often completed in cooperative groups in which learners assume a given role.
Whiteboard
A graphic display that can be shared by two or more users on a network.


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Table of Contents
  1. Introduction
  2. Applications in K-12 Education
  3. Benefits of Distance Learning
  4. Connectivity Issues and Alternatives
  5. Overview of Distance Learning Technologies
  6. Print Technologies
  1. Audio/Voice Technologies
  2. Computer (Data) Technologies
  3. Video Technologies
  4. Implementing Distance Learning
  5. References
  6. Glossary


Produced by the Florida Center for Instructional Technology,
College of Education, University of South Florida © 1999, 2009.