Link here for the Glossary

 Link here for the Standards for Ethical Practice of WebCounseling

Link to Internet Addresses

Link to Resources

Link to Computer Literacy Self Survey

Link to Web Site URLs for Regional RCEPs, CRP-RCEPs and DBTACs

Document Links Menu

Table of Contents  -  Introduction  -  Chapter 1  - Chapter 2  - Chapter 3  -  Chapter 4  - Chapter 5 

Glossary - Standards for Ethical Practice of  WebCounseling  - Internet Addresses - Resources

Computer Literacy Self Survey  - Web Site URLs for Regional RCEPs, CRP-RCEPs and DBTACs

Link here to email  Leon Oehlers, MS, CRC - Region 6 RCEP Webmaster to report broken hyperlinks, new URLs, and/or additional information:  loehlers@rcep6.org

     This glossary is not all-inclusive. It is composed primarily of terms used in the primer developed by Fudell and Hardy at the University of Texas (http://www.utexas.edu/cc/cit/de/deprimer). For an excellent listing of multiple glossaries related to the Internet/World Wide Web terms, telecommunication terms, digital terminology, and distance education terms, visit the University of Wisconsin-Extension Distance Education Clearinghouse (http://www.uwex.edu/disted/glossary.html).

analog: A means of storing and transmitting sound, pictures, or other material as an electrical wave (or waveform) that is a facsimile, or analog, of the original signal. This analog signal, or waveform, may be amplified, attenuated, or otherwise altered but retains the characteristic of its original signal. Example: The sound that comes from my stereo speakers is basically the same waveform that was created by the microphone in the studio, even though it has been stored on a phonograph record. See also digital.

aspect ratio: The ratio of width to height of a pixel or display screen. Display screens are usually about 5:4, although square pixels (1:1) are considered preferable.

asynchronous: Communication characterized by time-independence. That is, the sender and receiver do not communicate at the same time. Examples: electronic mail and voice mail.

audioconference: A conference, most frequently over the telephone system, between two or more remote locations with live audio transmission.

bandwidth: A measure of the capacity of a communications channel. The higher a channel’s bandwidth, the more information it can carry. Example: T1 has greater bandwidth than ISDN.

baud: A communication channel’s maximum information-carrying capacity in symbols (state or level transitions) per second. The baud rate coincides with bits per second only for two-level modulation with no framing or stop bits. The term causes much confusion, and it is preferable to refer to "bits per second" (bps), "bytes per second," or "characters per second."

bit: A binary digit. The unit of information that can take one of two values, such as true or false or zero or one.

BRI: Basic Rate Interface. An ISDN channel consisting of two 64-Kbs "bearer" channels for voice or data and a 16-Kbs control channel.

broadcast quality: An ambiguous term generally used to describe a video signal of high quality. Strictly speaking, however, broadcast quality defines a signal meeting FCC criteria for broadcast. Example: This amateur VHS camcorder footage is not broadcast quality because the quality of the recorded signal is not good enough to merit using it in our video program.

byte: The smallest addressable unit of digital storage larger than a bit and smaller than a word. A byte now consists of eight bits.

codec: A hardware circuit that converts analog video or audio signals into digital code and vice versa. A codec (short for COder-DECoder) uses techniques such as delta modulation and pulse code modulation.

compressed video: A method currently used to transmit images electronically. Compression of sequences of images is necessary because of the huge volume of digital information inherent in video. For instance, a CD-ROM with a memory capacity of about 650 megabytes can store only 30 seconds of a video segment without video compression. With compression, an approximately 70-minute-long video program can be stored.

computer conferencing: Interactive sessions between networked computers whereby data, documents, and/or video and audio are shared. The term encompasses both data conferencing and desktop video conferencing. Web chat, whiteboards, and Web-based conferencing may be used in computer conferencing.

desktop publishing: Utilization of microcomputer-based technology for the preparation of printed materials. Example: Using Adobe PageMaker or Quark XPress to design and lay out a newsletter for printing.

dialable: A line that can be dialed much like a telephone to any other site that has compatible equipment. Contrast to fixed connections, which always connect the same two points.

digital: A method of recording, transmitting, or reproducing sound, pictures (video), or other material by sampling an analog signal and translating those samples into digital information, or data. The digital signal, as opposed to an analog signal, bears no resemblance to its original form unless it is converted back into analog form. Example: Unlike with my old phonograph, the musical information on my CDs is a bunch of binary data that bears no resemblance to the sound waves that were present in the studio and picked up by the microphone.

e-mail: Electronic mail. The system whereby messages are automatically passed from one computer user to another through computer networks. Most e-mail systems allow "attachments" of files of different formats to be sent along with the text in the message body.

frequency response: A term describing by frequency limits the reproduction or transmission characteristics of a device or circuit. Example: The frequency response of an audio CD is 20 hertz to 20 kilohertz, which is nominally the same as human hearing.

GIF: Graphics Interchange Format. A standard format for compression of images. Images on Web pages are commonly stored in the GIF or JPEG formats.

hertz: Standard measuring unit for frequency measured in cycles per second. Named for Heinrich Hertz, a German physicist. Abbreviation: Hz.

HTML: Hypertext markup language. Coding used to publish documents on the World Wide Web which allows links to information in files on any computer connected to the Internet.

Internet Explorer: A Web browser software developed by Microsoft.

Inverse Mux: A device used to combine, or bond, ISDN channels to allow greater bandwidth, as required for a compressed video transmission. Also known as an IMUX or Inverse Multiplexer, an Inverse Mux is used on both ends of the transmission to allow the codec to "see" the aggregate bandwidth instead of the separate bonded channels. Example: Since we acquired an Inverse Mux at the UT Network Operations Center, we can transmit multichannel ISDN videoconferences to and from anyone similarly equipped.

ISDN: Integrated Services Digital Network. A fairly recent offering in the telecommunications industry, ISDN is a dialable, digital service available to most residences and businesses that offers much higher bandwidth than standard telephone service. ISDN lines come in two basic formats, BRI (Basic Rate Interface, capable of 128k of bandwidth, several of which can be aggregated by an Inverse Mux) and PRI (Primary Rate Interface, capable of 1472k bandwidth). Example: We got so tired of waiting for Web pages to download over our telephone modem line that we got an ISDN line that’s much, much faster.

JPEG: Joint Photographic Experts Group. A standard format for compression of images. Images on Web pages are commonly stored in the JPEG or GIF formats.

kilo: Thousand (10³). Abbreviated "K." Since computer specifications are usually binary numbers, it often refers to the precise value 1,024.

Kbps: Kilobits per second. Example: The telephone companies commonly use a 64 Kbps channel for digitized two-way voice conversations.

KBps: Kilobytes per second.

LAN: Local-area network. A computer network that spans a local area such as a building or campus. See also WAN.

Listserv: Mailing list management software that scans e-mail messages for the words "subscribe" and "unsubscribe" to automatically update the list.

mailing list: A list of e-mail addresses grouped together as an alias such that a message sent to the list goes to the entire group. Some mailing lists are simple "reflectors" which redirect mail sent to them to the list of recipients. Others are "moderated" or filtered by humans. Mailing lists allow members of a class to collaborate on a project without ever needing to meet face-to-face. Majordomo, Listproc, and Listserv are mailing list processors.

microwave: High frequency radio waves used for point-to-point transmission of audio, video, and data. A straight line of sight between the sending and receiving antennas is required.

modem: An electronic device that converts serial data from a computer into an audio signal in order to transmit data over a telephone line.

Netscape Navigator: Web browser software developed by Netscape.

Network: A set of nodes, points, or locations connected by means of data, voice, and video communications for the purpose of exchanging information.

NTSC: National TV Standards Committee. Administered by the FCC, this U.S. colored television standard broadcasts at 525 lines of resolution that are transmitted at 60 half frames per second.

on-line: Available for immediate use. Example: I tried to get on-line with my Internet service provider, America Online, but I was unsuccessful.

packet: A data unit sent across a network.

packet switching: The system that enables data to travel expediently across a computer network by breaking messages into packets which are individually routed between hosts, with no previously established communication path. Packets are routed to their destination through the most expedient route. The packets of a single message may follow different routes. The destination computer reassembles the packets into their appropriate sequence. Packet switching is used to optimize the use of the bandwidth.

POTS: Plain old telephone service.

PSTN: Public switched telephone network. The public telephone network.

Quicktime: Multi-platform multimedia software developed by Apple that delivers synchronized graphics, sound, video, text, and music.

RF: Radio frequency. Radio frequencies are electromagnetic signals that range from microwave to radio in length.

satellite conference: A conference between different locations where the communications links are made between orbiting satellites and various points on earth. Communications satellites provide telephone, television, and data services between widely separated locations such as universities or television stations in different cities. The technique involves the transmission of signals from an earth station to a satellite. The satellite has equipment that receives the signals, amplifies them, and transmits them to earth. Receiving stations then pick up the signals and provide the communications link.

streaming: Playing video or sound in real time as it is downloaded over the Internet. Data is decompressed and played (by use of a Web browser plug-in) as it is transferred to your computer over the World Wide Web. Streaming requires a powerful computer and fast connection since the file is not stored on your computer.

synchronous: Communication occurring between parties that are temporally synchronized. That is, communication that occurs between people at the same time, although not necessarily in the same place. Example: Internet chat is synchronous; e-mail is asynchronous.

T1: A general term for a digital carrier, typically leased from a local or long-distance provider, capable of transmitting 1.544 Mbps of electronic information. A T1 line is point to point, as opposed to a dialable ISDN line. T1 lines may be used fractionally or at their full bandwidth. E1 is the approximate European equivalent, prevalent also in Mexico. Example: The UT video network is composed primarily of leased T1 lines that carry compressed video and Internet data between UT components.

transponder: The part of a communications satellite that receives transmission from the ground (an up-link site) and retransmits it back to earth (a down-link site). Example: On the C-band satellite Galaxy 9, orbital location 123 degrees west, transponder 22 operates at a frequency of 4140 MHz and has horizontal polarity.

ubiquitous: Existing or being everywhere at the same time.

up-link: The process of sending video, or data, up to a communications satellite, where it is down-linked to a receiving site. Example: The local PBS station is going to up-link our teleconference so that it will be viewable by anyone with a C-band dish.

URL: Uniform resource locator. An address on the World Wide Web. For an excellent listing of multiple glossaries related to the Internet/World Wide Web terms, telecommunication terms, digital terminology, and distance education terms, visit the University of Wisconsin-Extension Distance Education Clearinghouse (http://www.uwex.edu/disted/glossary.html).

Usenet: A distributed electronic bulletin board system which allows users to post and read articles on it. It is international in scope and is probably the largest decentralized information utility in existence. Newsgroups, postings on Usenet, provide a mechanism for class collaboration and communication.

videoconference: A video communications session between two or more remote locations, with live, animated image transmission and display. TechWeb Technology Encyclopedia provides a more detailed definition and history of videoconferencing, including a discussion of various protocols and systems.

WAN: Wide-area network. A computer network that connects LANs or single computers in different geographic areas together.

Web chat: A system that allows two or more logged-in users to set up a typed, real-time, on-line conversation across the World Wide Web.

Web page: A location on the World Wide Web, identified by a URL, which contains a block of data. A Web page is stored on a server as a file written in HTML. Web pages for distance education classes often provide a course syllabus and hypertext links to related Internet resources and class materials.

whiteboard: An electronic bulletin board which allows users across a network to collaborate in real time.

World Wide Web: A distributed information retrieval system in which documents formatted in hypertext markup language are linked via hypertext transfer protocol to other documents, as well as audio, video, and graphics files. By using a Web browser and clicking on hot spots, computers are connected across the Internet. Use of the Internet has exploded with the development of Web browsers such as Mosaic, Netscape Navigator, and Microsoft’s Internet Explorer, which use a graphical user interface.

X.25: An OSI (Open Systems Interconnect) standard protocol which describes how data passes into and out of public data communications networks. Other protocols related to packet switching are X.3, X.28, X.29, and X.75.

XModem: A widely available protocol used for file transfer between modems. Also referred to as the "Christensen" file transfer protocol, XModem uses 128-byte packets with error detection. It is fairly slow but reliable. Improvements to the protocol were made and released as YModem and ZModem.

YABA: Yet Another Bloody Acronym. Used in response to statements like "I transferred the JPEG file over the POTS line since I didn’t have access to an ISDN or T1 connection."

YModem: File transfer protocol between modems which can use larger packets (1 kilobyte) than those used in XModem (128 byte).

ZModem: A modem file transfer protocol with error checking and crash recovery.

zip: A compressed archived file created by PKWare’s PKZIP or a compatible archiver. Compressing files allows faster transport across computer networks.

Link to Top of Page

Document Links Menu

Table of Contents  -  Introduction  -  Chapter 1  - Chapter 2  - Chapter 3  -  Chapter 4  - Chapter 5 

Glossary - Standards for Ethical Practice of  WebCounseling  - Internet Addresses -  Resources

Computer Literacy Self Survey  - Web Site URLs for Regional RCEPs, CRP-RCEPs and DBTACs

End of Page.