ActiveX
A
set of rules designed for controlling Windows applications which can be
downloaded and run on a browser. ActiveX is only supported on the
Microsoft Explorer browser.
Agent
A
program which moves from server to server on the Internet and accesses
resources in the name of the person who started it. Agents can perform
certain tasks such as collecting news, gathering stock quotes, etc.
Intelligent agents can learn what people like and dislike about the
information that the agent finds for them and use this information to
locate material more interesting to the agents user.
Alpha
An early attempt
to produce a working program is often known as an alpha version. Alpha
versions of software are usually versions which are released for testing,
generally alpha versions will contain a large amount of
bugs.
Applet
A Java program which is sent to a browser which can then
run the program using a built in interpreter. Applets can do almost
everything that a normal program can do, such as process data and draw
graphics. The browser must be able to handle Java in order to run the
applet.
Archie
An
Internet based system designed to automatically gather and index
information available on the ftp servers of the Internet. It can also be
accessed to look up where specific files are located.
Archive
In general
terms an archive is a storage place for data which is no longer needed. An
archive file is when a number of files have been merged into one file by a
special program called an archiver. This archive file also contains
information indicating how the files it contains were named and arranged.
The most common archivers are ?pkzip? (PC), ?tar? (Unix) and ?stuffit?
(Macintosh). Pkzip archives are placed in files which end in ?zip?, tar
archives are placed in files which end in ?tar? and ?stuffit? archive
files end in ?hqx?.
Asynchronous
communication
A method of communication where messages are sent and
received over a time period. An analogy would be posting a letter, the
writer creates and sends the letter. The receiver waits for the letter and
sends a reply when it is received. Asynchronous communication usually
appears in the computer world as email. Email is usually personal
asynchronous communication in that email is sent from one person to
another. A method of sending asynchronous communication that involves
larger amounts of people , i.e. one person sends a message to many, would
be a bulletin board, a list server or Usenet
News.
Audiographical
A form
of instruction technology which uses a shared graphic area to draw
pictures and create text (such as a whiteboard) as well as providing an
audio connection. The audio connection can be carried over the network or
via a telephone line. This means that an educator can present their
lecture material on an electronic page which can be seen by all the
students and give a spoken commentary on the
material.
Bandwidth
A measure of
the amount of data per second which can be carried by a network
connection.
Benchmark
A system
used for comparing the performance of different computer components
(software, hardware and networks). A benchmark usually consists of a set
of programs which are run on different components. Various results can be
taken from running benchmark programs, such as the time taken for the
benchmark to run, and these can be used to estimate the relative
performance of the component.
Beta
A program which
is still in the process of being developed. A beta version of a program is
usually made available for people to use so that the writers of the
program can get feedback on what people think of the product or whether it
contains any bugs. Beta versions of software are refined alpha versions,
i.e. some of the bugs present in the alpha version have been
removed.
Browser
A piece of
software which is designed mainly to read text and display pictures and
other multimedia information. The browser usually receives the information
it is to display written in a special format (called HTML) and prints it
out in a window on the users screen. Think of it as a program which
translates information written in a special format into a viewable page.
Using a browser on a computer connected to a network allows files from
other computers to be copied to your computer and displayed by a browser.
Browsers also come with extra facilities which allow them to display
pictures, video clips and to play sounds. Some browsers will need to use
extra software on your computer to do all these things whereas others will
have everything built-in. Most current browsers are graphical in that they
can be used to display graphical information (pictures, videos, etc.) but
text based browsers, such as Lynx, which will display text only are
available.
Bug
A mistake made by
the writer of a computer program which causes it to
malfunction.
C
A computer
programming language. Programs written in C are translated into a form the
computer can understand using a program called a compiler. Originally
designed to write operating systems, C is the worlds most popular
language, mainly due to its efficiency and
flexibility.
Cache
A cache is an
area of the computer, either in memory or on disk, where information which
is not currently being used is stored in the hope that it will be needed
again soon. The purpose of this is to speed up future accesses to the
data. Browsers can maintain caches of recently accessed pages and images,
so can Web servers.
CD-ROM
Compact Disk
Read Only Memory. An ordinary compact disk (CD) which contains data which
can be read by a computer. CD-ROMs can only have information read from
them once they are created. A CD-ROM is popular because it can hold a
large amount of information (~650Mb). The peripheral necessary for
creating a CD-ROM is called a CD Burner.
CERN
The
European Laboratory for Particle Physics. Usually associated with the CERN
Web server and the development of the WWW. CERN no longer produce Web
software, their products are now managed by the W3 consortium.
CGI
(Common Gateway Interface)
A standard developed to allow http
servers to receive and process information from Web browsers. Information
is usually sent using a form displayed on the browser, e.g. the user fills
in the answers to a quiz on a browser page and pushes a button to send the
information to the server. A CGI program is a program which the server
calls to deal with this information. The name of the CGI program is
supplied by the browser with the information it sends. When a CGI program
is called it will run on the server, process the information sent to it
and return information to the browser, usually in the form of HTML. So,
for example, you could fill out your quiz in your browser, push a submit
button which will send the answers to the quiz to a CGI program on the
server which will compare the answers it receives from your browser with
the right answers and cause a list of mistakes to be sent to your browser
which will then appear on your screen. CGI programs can be written in a
number of languages, the most popular being Perl and C
.
Chat tools
Programs
which allow synchronous communication between individuals or groups. Chat
tools usually consist of an area on screen where users type their messages
and view messages sent by other users.
Clickable Image
Map
Another name for an Image
Map.
Client
1. A
computer system or a computer program which relies on another computer
(called a server) to provide it with information or a service such as disk
space or access to a network.2. A program which connects to a server
and requests something. An example of a client program would be a
browser.
Client-side
An
operation which is performed using the users browser or on the users
computer. A client side operation is designed to minimize the number of
accesses made to a server and the load placed on a server. Examples of
operations which can be performed client-side are image maps and form
processing and preprocessing. Operations which are performed by the server
are known as server-side operations and are handled by a CGI
program.
Compressed video
The
result of an operation known as video compression. A video is taken and
put in a file in a form that ensures that the file is as small as
possible. It works on the principle that only certain information changes
from one frame of a video to another so it does not store information
which does not change.
Compression
The
translation of a file into a form which takes less space. This means that
the file will also be quicker to transmit. A special program performs the
compression of a file and another program is usually required to translate
the compressed file into its original form. Translating the file back into
its original form is known as decompression.
Computer-Mediated-Communication (CMC)
Communication that
takes place through, or is facilitated by, computers. It can involve
asynchronous communication mechanisms such as email and usenet or
synchronous communication such as chat tools and talk.
Computer Based
Training
The use of a computer to train people. The training
material used by such a system is known as
courseware.
Computer Supported
Cooperative Work (CSCW)
The idea that computers and software
can be used to support people who wish to work in a group. Software which
facilitates group work, commonly known as groupware, usually contains such
features as: bulletin boards, email facilities, common work areas,
document sharing and version
management.
Cyberspace
A term for
an electronic world. People who spend time communicating with others
virtually (i.e. via email or chat tools) are said to be in a different
plane of existence, a cyberspace.
Daemon
A program
designed to handle various computer tasks without needing any help from a
human. When a daemon is started, often automatically when the computer
first starts up, it waits until it is needed to do a job and then
executes. Examples of daemons are printer daemons which wait until
somebody tries to print a file, handles the sending of the file to the
printer and then return to waiting until they are needed
again.
Database
A
collection of records, which store information, kept on a computer. A
database can contain many kinds of information, student records, stock
records, etc. The program used to add data and manage the computer files
which make up the database is called a database management
system.
Default
The
standard settings for a piece of software or hardware. Most software will
come with certain settings predefined, the user can change these settings
or leave them as they came.
Dial up connection
The
method of connecting to a computer network using a modem and a phone line.
Domain
Part of the
Internet address. The domain usually specifies the organization that the
computer is attached to and the country where that computer is located.
For example the computer whose full name is ?webclass.ucc.ie? is attached
to the organization ?ucc? in the country ?ie?
(Ireland).
Domain Name Server
A
computer in an organization which is responsible for managing the names
and IP numbers of local computers. It will usually have a connection to
the other domain name servers on the Internet using the domain name
system.
Domain Name System
A
system of looking up computers names in order to obtain their IP number.
Each computer in the system is known as a Domain Name Server and maintains
a list of local computers and their IP numbers. The domain name system has
a protocol for querying all relevant Domain Name Servers until it finds
the information for the requested computer or establishes that the
computer does not exist.
Download
The copying
of a file from one computer to another using a network is known as a
download.
Think of it as if you were going shopping, you download
goods into your shopping basket.
E-mail
Electronic
mail. A method of sending text messages to people who have access to a
computer. Mail messages are composed using a text editor and sent via
computer networks to a persons address. An email address is the postbox
that is used to store email sent to you. This postbox is kept on computer.
An email address looks like ?joe@acomputer.org? (which means that mail is
sent to a person called joe whose mailbox is kept on the computer called
?acomputer.org?).
Encryption
A method of
translating information into a form which nobody can understand unless
they have a ?key? which will allow them to translate the information back
into its original (understandable) form.
The process of translating
information into an unreadable form is called encryption, the process of
translating the unreadable information (called the encrypted information)
into something understandable is called decryption. This system can be
used to ensure that people cannot read your messages as the messages are
transmitted around a network.
Ethernet
A popular
method of networking computers in a LAN.
FAQ
(Frequently Asked Questions)
A list of commonly asked questions
about a particular topic. The idea originated in Usenet News so that new
users could be directed to a resource which would answer the majority of
their common questions.
A list of FAQs can be found at:
http://www.lib.ox.ac.uk/internet/news/faq/by_category.index.html
Firewall
A firewall is
a computer which implements a security system. Computers ?behind? the
firewall can access other computers on the Internet but Internet computers
are prevented from accessing any computer behind the firewall. Think of it
like a trapdoor, people can send things through one way but things cannot
come from the other side of the
trapdoor.
Flame
An abusive
message, usually sent in response to an inappropriate comment on a
newsgroup. Flame wars are the Internet equivalent of shouting matches.
Unfortunately on many newsgroups there is no referee so flame wars can
rage for considerable periods of time.
Form
A page of HTML
which can contain boxes where the user of the browser viewing the HTML
page can fill in information and have it processed, either by a server or
a program contained in the HTML page. Forms can contain such elements as
text boxes, where you type in text, radio buttons, which you click on and
off, etc.
Frame
Frames can
be used to divide a HTML page up into independent parts. Each part can
then display information separate of the others. For example, you could
create two frames, one a list of contents the other a page of text. By
clicking on various links in the list of contents the page of text could
change but the table of contents frame will always stay the
same.
Freeware
Computer
software which is freely distributable and usable without
charge.
FTP
File Transfer
Protocol. This is a protocol to allow the transfer of files from one
computer to another over a network. One computer will run an ftp server
which allows people on other computers run ftp client programs to connect
to it and upload and download files.
Gateway
Also know as a
router this is a computer which acts as a link between other computers. It
forwards information it receives from one set of computers to another
according to a set of rules called a
protocol.
GIF
Graphics
Interchange Format. A form of compression used for
pictures.
GNU
license
A licensing agreement which accompanies certain
software. It is designed to ensure that the software can be copied and
distributed freely.
Gopher
An early form
of computerized information distribution system. Gopher is a protocol
which allows a computer to maintain a database of information which can be
searched by other computers which connect to it using the Gopher protocol.
Gopher works on a menu based system.
Home page
A
document on the Internet, written in HTML, that represents the top level
of any related pages. It is like the foyer of a business, the hallway of a
home. It is designed to be the first page that a person sees when they
access a particular Web address. Home pages are usually given the name
?index.html?.
HTML
HyperText Markup
Language. A HyperText formatted document. The language consists of a
collection of commands used to format text. The commands are enclosed in
?tags? (placed between a < and a >). HTML can be interpreted by
browsers and is used to ensure there is a standard way of preparing
documents to be viewed on the Web. There are different ?standard? forms of
HTML which browsers can translate into a viewable
page.
HTTP
HyperText
Transport Protocol. The name of the protocol which transfers information
around the Web.
HTTP Server
A program
which executes on a server and allows browsers to access information
stored on the server and to execute CGI programs. The program is called a
HTTP server because it uses the HTTP protocol for communicating with
browsers.
HTTPS
Secure
HTTP, a version of HTTP which encrypts the information being transmitted
over the Web to prevent unauthorized people reading it.
Hybrid
In the
context of this book a hybrid is a method that combines two or more
methods or systems. For example an on-line course can contain components
which are stored on a students own computer and components that are stored
on a server.
Hypermedia
An
addition to the idea of hypertext to include sound, video and
pictures.
Hypertext
A
collection of pages of information which contain cross-references or links
to other documents, which, with the aid of a browser program, allow the
reader to access one document from another by selecting the
links.
Icon
A small
picture, it usually denotes the action performed if you click on it. For
example an icon of a house will take the user who clicks on it to the home
page for that particular site
ICT
Information and
Communication Technology: In the past we had IT, but by adding the C , we
and others express that Communication is the central issue, if you want to
make IT a succes.
Imagemap
A
graphic image which is part of a HTML page. Predefined parts of the image
can act as links to other HTML pages. These areas, called regions, are
defined by a program called an imagemap editor. This imagemap editor can
be used to select different sections of any picture and link them to some
other HTML page. This means that different parts of the image will link to
different pages, e.g. imagine a picture of a signpost, clicking on the
name of a town on the signpost will bring us to that town. The result of
clicking on an image map is either processed by the computer (client side)
or sent to the server (server side) depending on the browser type and the
information which accompanies the image map.
Information Overload
A
phenomena whereby an individual treats a large amount of information with
equal priority and becomes confused and overwhelmed. For example, say you
walked into a library with hundreds of thousands of books, how do you
decide which book is relevant, do you try to read and understand all the
books ? This is what happens with information overload, the ease with
which students can electronically call up vast amount of information means
that students sometimes attempt to process all of the information,
regardless of its relevance.
Instructional
Television
The delivery of lectures using a video or ?live? using a
television channel.
Interface
A
boundary across which two systems communicate. An interface can be a
hardware device (e.g. the cable from your computer to your printer would
be an interface) or it could be a software interface. A software interface
governs how the user will control a program and how the program will
display results. For example a Graphical User Interface is a method of
communication between a person and a computer which uses pictures, your
files look likes pages, your directories look like folders and you click
on a picture of a program to make it run.
Interlaced GIF
An
image file in the GIF format included as part of a HTML page. The
interlaced GIF will initially load into the browser at low resolution and
then, as more of the image is loaded, will become clearer. Interlacing
GIFs are used for a fade in type effect.
Internet
The
world?s largest WAN, a global system of interconnected computers connected
via different types of computers but using a common protocol for
communications. Like the phone system it enables computers all over the
world to pass information to each other. The Internet consists of a set of
links between machines. Usually information is passed from one link to
another through routers which are computers which decide where to send the
message and which route to send them by.
Internet
Phone
A system whereby users can use the Internet to carry real
time voice communication, i.e. a phone conversation.
Internet Service Provider
(ISP)
Usually a commercial company which provides users with a
point of presence which they can connect to using a modem. The user then
has access to the Internet through this system.
Intranet
A
networked system which uses the same protocols as the Internet but is
confined to a particular organization. This means it provides the same
services as the Internet without being connected to the Internet.
Intranets are a more private means of exchanging information within a
local area.
IP Number
Internet
Protocol number. Each computer on the Internet must have its own unique IP
number to enable it to receive messages intended for it and to be able to
access resources which are reserved for it. The computer equivalent of a
telephone number.
IRC (Internet Relay Chat)
Just like a CB radio system except it operates over the Internet
and users must type their conversations.
ISDN
Integrated
Services Digital Network. A type of phone line designed to handle digital
information (the format that computers use to store and transmit data). It
can transfer data between computers more than twice as fast as an ordinary
phone line.
Java
A
general purpose programming language developed by Sun Microsystems. Java
programs are converted into ?applets? which can be executed on browsers
which are capable of handling them. This enables Java programs to run on
any operating system which will can run a browser capable of handling
Java.
JavaScript
A
language which is intended to be included as part of a Web page.
JavaScript programs can run on any browser capable of handling them.
JavaScript programs can do simple tasks such as perform calculations but
are not as powerful as the Java language. The JavaScript program is
contained in the HTML page that a browser displays. JavaScript was
proposed by Netscape and is usable on more recent versions of their, and
other companies, browsers.
JPEG
Joint
Photographic Experts Group. A form of compression used for pictures. JPEG
pictures can be displayed as part of a Web
page.
Jscript
Microsoft?s
version of JavaScript. It runs only on the Microsoft Explorer browser.
Knowledge Map
A
graphic representation of a knowledge area and the relationships that are
present in it.
LAN
Local Area
Network. A network of computers which is used in a small geographic area
(usually <1km). It usually uses the Ethernet protocol to send messages
from one computer to another and is considerably faster than most
WANs.
Learner Centered
A
method of teaching which is based on the student. The student decides what
to learn and the pace at which the learning is carried
out.
Link
A means of
putting a reference (link) from some point in one hypertext document to a
point in another document or to a different place (e.g. a different
section further down the page) in the same document. A browser will
usually display a hyperlink in some special way, e.g. it will write it in
a different color. When the user selects or ?activates? the link the
browser will go to the point contained in the link. A link is usually
activated by clicking on it with the mouse pointer.
Link
A means of
putting a reference (link) from some point in one hypertext document to a
point in another document or to a different place (e.g. a different
section further down the page) in the same document. A browser will
usually display a hyperlink in some special way, e.g. it will write it in
a different color. When the user selects or ?activates? the link the
browser will go to the point contained in the link. A link is usually
activated by clicking on it with the mouse pointer.
Lynx
A popular
text only browser.
MIME
Mulitpurpose
Internet Mail Extensions. A method of transmitting information in
particular formats over the Internet, it was originally designed to allow
the attachment of various applications and file formats to mail messages.
For example, pictures have their own mime format which enables browsers to
recognize them.
Mirror
When an
exact copy of a set of files on one site is kept on another it is known as
a mirror. The idea of a mirror is simple. Say that someone made a file
available for downloading in outer Mongolia, this is quite far away and
will take some time to reach over the network so someone else will get a
copy of that file (or files) and put it on a computer closer to you so
that it takes less time to access. A mirroring system means that every so
often the computer nearest to you will check the original computer to see
if any of the files have changed. If they have then the mirror program
replaces the old copy with the newer
copy.
Modem
MODulator-DEModulator. A electronic device
which facilitates communication between two computers over a phone line.
It converts the usual method that computers use to communicate (binary)
into a form which can be sent over an ordinary telephone line and performs
the reverse operation on any data it receives. Modems can transfer data at
different speeds, e.g. 28.8 thousand (k) bits per
second.
Moderator
A person
who is in charge of a mailing list or a newsgroup. A moderators duties
could involve: maintaining a list of members, filtering or pre reading
messages to see if they are appropriate and acting as
referee.
Mosaic
The
original graphical Web browser developed by the National Center for
Supercomputing Applications.
MOV
A file format
developed by Apple computers to enable storage of compressed
video.
MPEG
Moving
Pictures Experts Group. A standard used for compressing videos.
Multimedia
A
presentation which takes place in the form of sounds, text, pictures and
videos.
Network Computer
A
very basic (and therefore cheap) computer which is designed to rely on a
server to store all the information it needs. Network computers are
designed to take advantage of the fact that an expensive client computer
may be wasted doing simple tasks and may need to be linked to a network to
communicate anyway.
Off-line browser
An
off-line browser is a computer program which can translate HTML into
readable text and pictures but does not need to be connected to a network
(on-line usually means connected to a network). Using an off-line browser
means files written in HTML can be displayed on computers which have no
network access.
Online course
The use
of computers and a network (such as the Internet) for conducting a
learning course. The network could provide synchronous and asynchronous
communication facilities. Students can link up, usually using a browser,
to a server which acts a repository for course information and as
mechanism for facilitating communication.
PDF
Portable
Document Format. Developed by Adobe, PDF is a file format for a document
which means the document can be displayed in the form it was created no
matter what platform or set-up the user is using. PDF files are usually
displayed using a utility called Acrobat.
Peripheral
A part
of the computer system which is not strictly part of the main computer.
Such a part may be connected to sockets in the computer and perform some
specific function, e.g. a printer is a peripheral. Some peripherals may
require you add extra components and software to your
computer.
Perl
Practical
Extraction and Report Language. Perl is a general purpose programming
language most frequently use for scanning text and printing reports. Perl
programs are not converted into machine code like C programs but require a
special program, called an interpreter, on each computer they are executed
on. The interpreter will take the Perl language and translate it into
machine code. This means Perl code can be written in a standard way and
used on any machine which has a Perl interpreter available for
it.
Personal Digital Assistant
(PDA)
A small hand held computer, most are the size of large
calculators. Originally designed to store memos and keep track of
appointments they are now being used to send email (using a connection to
a network through a mobile phone) and some even come with browsers. Their
screen size traditionally limits their use for serious reading. Input is
usually via a small keyboard or by using a special pen to write on the
screen which the PDA will interpret to produce
text.
PGP
Pretty Good
Privacy. A system for encrypting
information
Platform
Used to
refer to a specific computer or operating system, e.g. a Macintosh is a
platform. The phrase ?platform independent? means that a piece of software
should work on a computer no matter what its operating system or
make.
Plug-in
A piece of
software used as part of a Web browser to extend the browsers
capabilities. Plug-ins perform some task that the Web browser cannot, e.g.
a plug-in can be used to play sound files or show a
video.
Point of presence
A
computer or telecommunications router which is connected to using a modem.
The point of presence is used to gain access to an Internet Service
Provider. Points of presence are an attempt to reduce the phone costs of
computer users who must use modems and phone lines to access the Internet.
So for example an Internet Service Provider could set up points of
presence in all major cities saving users the expense of dialing into one
central site which may be thousands of miles
away.
Point to Point Protocol
(PPP)
Point to Point Protocol. A communications protocol used with
a modem. It allows users computers to communicate with their local
Internet Service Provider.
Portable
A program
is said to be portable if it is platform independent or it can easily be
altered to run on different platforms.
Protocol
A series
of rules. Protocols govern how information being transmitted is formatted
so people who write programs can use the protocol to decide how to store,
receive or transmit information.
Proxy server
Due to
security concerns and administrational reasons not all the computers using
the Internet are connected directly to it. A proxy server is a computer
which is connected to the Internet and will accept requests from computers
which wish to access the Internet. Those without direct connections to the
Internet can forward the messages they wish to send to the Internet to a
proxy server which will transmit them to the Internet. The proxy server
will take any information that results from this request and send it back
to the original source of the request. Proxy servers are usually used for
security purposes. That is the person managing the proxy server can
control which computers can send and receive messages from the
Internet.
Public Domain
Software
Software which anyone can copy or use. The author has none
of the rights which apply to a copyright work.
RealAudio
A
way of storing sound for distribution over a network. RealAudio uses a
streaming system to ensure that the listener does not have to wait for the
whole file to download.
RFC
Request For
Comment. A technical document detailing a proposal for a standard
distributed to people interested in contributing towards the development
of an agreed standard.
Robot
A name for a
program which will explore the Web on its own collecting information.
Robots are usually used for searching for resources on the Web. Robots
which collect information for querying by users are also known as
spiders.
Router
Also know as a
Gateway this is a computer which acts as a link between other computers.
It forwards information it receives from one set of computers to another
according to a set of rules called a
protocol.
RTF
Rich Text
Format. A standard format developed by Microsoft for the conversion of
wordprocessor documents into a form which can be recognized by different
wordprocessors. RTF documents carry no specialized wordprocessor
information, such as macros, etc., but maintain formatting and embedded
objects such as pictures.
Scanner
A computer
peripheral used for translating paper documents into a form which the
computer can store and print out. Normally information read in is stored
in the form of a picture but by using Optical Character Recognition (OCR)
software a page of paper text can be translated into a page of text on the
computer and stored in a wordprocessor file which allows it to be
edited.
Search Engine
A
computer program run on a http server which searches a database,
consisting of the contents of other Internet sites, for information which
the person accessing it asked for.
Server
1. A computer
which is intended to allow other computers to connect to it and access
information stored on it or use its other resources. The idea behind a
server is that you can buy a powerful computer and use it to store
information and resources centrally so that people in the organization do
not have to keep a copy of the information on each computer they
use.2. A program running on a computer which acts as a server can also
be known as a server if its function is to receive requests from client
computers (or programs), process them and return information. Some
examples of servers are the http and
ftp.
Server-side
If a
browser does something which requires the server to perform an operation
this is know as a server side action. This means, for example, that if the
user clicked a server side image map the browser runs a CGI program on the
server which tells it what to do for the result of the click, i.e. what
page should be loaded if the user clicks on a certain area of the image
map.
Shareware
Software
which is distributed without charge for sampling purposes. Users of the
software are supposed to pay for if they intend using it. The author still
holds the copyright on the work.
Shockwave
A
multimedia plug-in for use with Web browsers.
Signature
A short
personal message usually found at the end of an email message. Mail
programs can be configured to automatically add a signature file to each
outgoing message. Signature files contain useful information about the
sender of the message such as their postal address, telephone number or
Web page URL.
Site
Another name for
a server.
Slip
Serial Line
Internet Protocol. A communications protocol used with a
modem.
Streaming
A method of
sending information to a browser to avoid a long wait by the user.
Streaming usually involves sending portions of a sound or video file which
can then be displayed by a browser and discarded when the next section of
the file arrives via the network.
Student Centered
A
method of teaching which is based on the student. The student decides what
to learn and the pace at which the learning is carried
out.
Subnetwork
The network
equivalent of a private road. Subnetworks consist of computers connected
over a private network which minimizes the amount of traffic which needs
to be carried on the network medium (the network cable). Computers in the
subnetwork can access other computers outside the network by using a
router or a proxy.
Surfing
A term for
moving around the WWW following various links and accessing various
sites.
Synchronous
Communication
Communication which takes place simultaneously, e.g.
a telephone conversation.
Talk
A program to
allow synchronous text communication over
networks.
Teacher Centered
A
method of instruction in which the teacher decides on the material to be
taught and the pace at which it is taught.
Telematics
Teaching
using a combination of telecommunications (telephone, radio) and
computers.
Telnet
A protocol for
linking two computers together. Connecting to another computer using
telnet allows you to use the other computer as if you were sitting in
front of it.
Throughput
The amount
of information a communications channel can carry. Usually measured in
bytes per second.
Transparent
GIF
A GIF which appears to float on top of the browser display
window as the background color of the GIF has been set to match the
browsers background color. See:
Upgrade
An improved
version of a software or hardware product. An upgrade is usually issued to
make a slight improvement to an existing product or to fix bugs which have
appeared since the product was released. Sometimes people are required to
pay for these upgrades.
Upload
Copying a file
from your computer to another computer via a network is called an
upload.
URL
Uniform
Resource Locator. A standard way (like a postal address) of referring to
an object on the Internet. A URL starts with the name of program on the
server being connected to which is used to fetch the object: FTP, gopher,
http. Next comes the address of the computer on which the object is
stored. Finally comes the location of the object on that machine. E.g. the
URL 'http://www.netscape.com/index.html' indicates that the browser asks
the http program running on the server called www.netscape.com for the
file called index.html.
Usenet
A system for
distributing text among cooperating computers. The text comes from various
asynchronous bulletin boards, known as newsgroups. Each news group is
devoted to a particular topic.
VBScript
Another
version of a programming language that forms part of a HTML page.
Developed by Microsoft and useable only on their Explorer browser it is
the same idea as JavaScript although the two are not compatible.
Virtual Reality
Using
a computer to mimic reality. The levels of complexity can go from drawing
3D pictures up to wearing helmets with built-in video screens which give
the impression that the user really is in a real
world.
Virus
A
computer equivalent of a human virus, a virus is a piece of code which
inserts itself into (or infects) other pieces of code. Viruses are usually
programmed to erase code or perform some other disruptive operation at
certain dates. Programs called virus checkers and virus screeners are
available to help protect your computer.
Visit
When you
access a HTML document on a remote server you are said to be ?visiting?
that computer.
VRML
Virtual
Reality Modeling Language. A method of enabling three dimensional ?worlds?
to be displayed on a browser. VRML is a programming language which is
placed in a HTML page and allows the browser to create a 3D picture. The
user can then change that picture by using navigation controls, e.g. they
can ?walk? forward through the world.
WAIS
Wide Area
Information Service. A form of database available on the
Internet.
WAN
Wide Area Network.
A network of computers which is distributed over a wide geographical area.
Usually computers linked together in a WAN are linked by one (or more)
telephone lines. The Internet is the worlds largest
WAN.
web
World Wide Web. A
collection of tools, usually Internet based which allow the transportation
of HTML related material. Browsers are used to access information
available on the WWW.
Web
TV
A method of hooking up a primitive computer to a
television and establishing a connection, via a modem, with the Internet.
The user can then use the Internet using a remote control to navigate and
their television to display information.
Whiteboard
A form
of communication where the participants have an area on their screen where
they can write, draw and paste graphics. This area is shared by the other
participants and can be viewed by
them.
ZIP
A
form of compression popular among Personal Computers.