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Following are the definitions of some common Internet terms. Search by the
first letter of the word you wish to know more about or scroll the entire
list. If you don't find the term that you are looking for here, send an
email to editor@upromote.com
and we will send the definition and add it to our expanding glossary.
Alternatively, you can
download the UPromote Terms Glossary in
.pdf format.(61 K, 16 pages)
Access Provider: The remote computer system to which you connect
your personal
computer and through which you connect to the Internet. An access
provider is the company that provides you with Internet access and
in some cases, an online account on their computer system. An
access provider can be a large commercial service like Compuserve
or America Online, which will charge you by the hour for your
Internet access, or a small local company, which might charge you a
flat rate per month for unlimited hours. If you access the Internet
directly from a company account, then your company is your access
provider.
The range of services and the cost can vary widely depending on
your geographic location and the number of service providers in
your area. Of course, there is no limit on the number of providers
you can have, and for various reasons you may find that you want or
need more than one provider.
Ad banner: An ad on a Web page, often using moving images and
sound as well as text. Clicking on a banner usually takes the user to an
advertiser's Web site.
Ad request: An ad request occurs each time the user's browser
requests information from an ad server. If a Web page contains an ad,
the browser will automatically request the information from the ad
server.
Ad view: Technically, an ad view (also called an exposure) occurs
every time an ad is requested from an ad server. Or, on the front end,
an ad view represents the number of times a banner ad is seen on a
Web page.
ARPANET: The computer network system that gave birth to the
Internet.
ARPANET (Advanced Research Projects Administration Network)
began in 1969 as a U.S. Department of Defense experiment in
packet-switched networking.
Backbone: A high-speed line or series of connections that forms a
major
pathway within a network. For example, National Science Foundation's
network (NSFNET) was, for many years, the backbone of the Internet. See
also Network.
Bandwidth: The maximum amount of data that can travel a
communications path
in a given time, usually measured in seconds. If you think of the
communications path as a pipe, then bandwidth represents the width
of the pipe that determines how much data can flow through it all at
once.
Binary File: A file that contains more than plain text (i.e.
photos, sounds, a
spreadsheet, or a formatted word-processing document). In contrast
to ASCII files, which contain only characters (plain text), binary
files
contain additional code information. A binary file is made up of
machine-readable symbols that represent 1s and 0s. Binary files
include sound files, graphics files, and software, and are frequently
called binaries.
This all becomes important when you wish to transmit a file over the
Internet. Let's say you want to download a neat piece of software
called "Fitware" to help you keep track of your fitness regime.
Depending on the software you use, you may find yourself
confronted with a choice of file formats to download. If the file is
a
piece of software (like the "Fitware" program), a sound file, or a
picture file, you will choose the "binary" option.
Bit: Short for binary digit, a bit is the smallest unit of data a
computer
can handle. Bits are used in various combinations to represent
different kinds of data. Each bit has a value of 0 or 1.
BPS: Abbreviation for Bits Per Second and a measurement of how fast
data is transmitted. BPS is usually used to describe modem speeds
or the speed of a digital connection. See ISDN; T1 Line and T3
Line.
Browser: A software program that allows you to view and interact
with various
kinds of Internet resources available on the World Wide Web. A
browser is commonly called a web browser.
Byte: A series of bits of a particular length -- usually 8.
Computer storage
space is measured in bytes. A Kilobyte (or 1K) represents 1024
bytes and a Megabyte (1Mb) represents one thousand "K" bytes, or
one million bytes.
Cache: When you download a web page, the data is cached, meaning
it is
stored temporarily on your computer. The next time you want that
page, instead of requesting the file from the web server, your web
browser just accesses it from the cache. That way, the page loads
quickly. But if the web page is updated frequently, as may be the
case with news, sports scores or financial data, you won't get the
most current information. By using the Reload button on your
browser, this timely data is updated by downloading fresh data from
the server.
Click-through: The number of times an ad banner is clicked on
during
a given period. Each time a user clicks on an ad banner--thus taking
that user to the advertiser's site--it represents one click-through, or
click.
Click-through rate: The percentage of times a banner ad is clicked
on out of the total number of ad views. If a Web page containing your
ad is seen by 10 users and one user clicks on the ad, the click-through
rate is 10 percent. Expressed mathematically as clicks divided by ad
views, the click-through rate is a measure of an ad's success. Often
shortened to click rate.
Common Gateway Interface (CGI):
The interface program that enables an Internet server to run
external programs to perform a specific function. Also referred to as
Gateway or CGI "scripts," these programs generally consist of a
set of instructions written in a programming language like C or
PERL that process requests from a browser, execute a program and
format the results in HTML, so they can be displayed in the
browser. Gateway scripts are commonly used to add interactivity to
a web page by allowing users to do things like fill out and submit
forms for processing (as in an order form for an online catalog);
query databases by submitting search requests; and register or gain
access to password-protected areas of a site. CGI scripts are also
used to implement a variety of tracking and measurement systems
on a web site.
Cookies: A cookie is a file sent to a web browser by a web server
that is used
to record one's activities on a web site. For instance, when you buy
items from a site and place them in a so-called virtual shopping
cart,
that information is stored in the cookie. When the browser requests
additional files, the cookie information is sent back to the server.
Cookies can remember other kinds of personal information --your
password, so you don't have to re-enter it each time you visit the
site; your preferences, so the next time you return to a site, you
can
be presented with customized information. Some people regard
cookies as an invasion of privacy; others think they are a harmless
way to make web sites more personal.
Most cookies have an expiration date and either reside in your
computer's memory until you close your browser or they are saved
to your hard drive. By the way, cookies cannot read information
stored in your computer.
You can use a text editor to view cookie files. For Windows users of
Navigator, the file is called cookies.txt and is located in the the
same folder as Netscape. Mac users can find it in the Netscape
folder in the System/Preferences folder. Explorer creates separate
files for each cookie and stores them in folders named "Cookies" or
"Temporary Internet Files."
CPM: Cost per thousand ad views. (The M stands for the Latin mille,
meaning "a thousand.") The cost of the ad per 1,000 ad views.
Dial-up Account: A type of account available for connecting to the
Internet. Having an
account on a computer system means you have a login name and a
password that lets you access some parts of that system. A dial-up
account through an Internet Service Provider allows you to use your
modem to make a connection to your provider's system. Once you
have dialed your provider's local number and are connected, the
provider then connects you directly to the Internet, where you can
run any Internet navigation software (like a web browser), just as
you would if you had a direct connection to the Net.
Different types of dial-up accounts are available. A SLIP or PPP
account allows you to navigate the World Wide Web directly from
your Windows or Mac operating system. A UNIX shell account
allows you to use UNIX commands on your service provider's
system.
Also see Access Providers.
Directory A system that your computer uses to organize files on
the basis of
specific information. Directories can be organized hierarchically so
that files appear in a number of different ways, such as the order in
which they were created; alphabetically by name or by type, etc.
Dithering: When working with a computer display system that
supports 8-bit
color (or fewer colors), the video card can display only 256
different
colors at one time. Dithering is a technique to simulate the display
of
colors that are not in the current color palette of a particular
image.
It accomplishes this by arranging adjacent pixels of different colors
into a pattern which simulates colors that are not available to the
computer.
Domain Name: The unique name that identifies an Internet site. The
Internet is
made up of hundreds of thousands of computers and networks, all
with their own domain name or unique address. Domain names
always have two or more parts separated by dots. A given server
may have more than one domain name, but a given domain name
points to only one server.
For example, "whitehouse.gov" is the domain name belonging to the
Whitehouse computer system. Once a system administrator
registers a unique domain name, subaddresses can be assigned to
the machines and people on the local network. So the President's
e-mail address is "president@whitehouse.gov," the
Vice-President's is "vice-president@whitehouse.gov," and so on.
Each corresponds to a unique IP address. The machine that serves
up the Whitehouse web pages is called www.whitehouse.gov.
Domain names typically consist of some form of the organization's
name and a suffix that describes the type of organization. For
example, IBM has registered the domain name "ibm.com"; Xerox
corporation has registered "xerox.com." Registration is on a first
come, first served basis. The domain name suffix is assigned based
on the type of organization. For U.S. domains, the suffixes are:
.com - corporations
.edu - educational institutions
.org - non-profit organizations
.mil - military organization
.net - network provider
.gov - government institution
In addition, non-U.S. sites have an additional extension that
indicates the country where the domain is located. For example:
.au - Australia
.dk - Denmark
.ge - Germany
.uk - United Kingdom
In the United States, domain names are assigned and indexed by the
InterNIC project (a joint project of the National Science Foundation,
AT&T, and Network Solutions, Inc.). Each of these addresses is
actually an alias of a numerical address (called an IP address). The
IP number for the Whitehouse for example, is 198.137.240.100. To
access the Whitehouse Internet site, you could use the IP number if
you like, but most people prefer to use the quasi-English domain
name alias "whitehouse.gov."
There is much more information about domain names available at
The InterNIC Home Page. To learn the IP address and to contact
names for a particular domain name (such as whitehouse.gov), use
the InterNIC WHOIS search form. You can also use this form to see
if anyone has registered a domain name you may be considering.
DPI (Dots Per Inch): A measurement of print image resolution and
quality. A larger
number of dots allows for more detail and therefore a higher
resolution image. The average laser printer has a resolution of 300 x
300 dpi which means it can print 300 dots per inch horizontally and
300 dots per inch vertically, 90,000 dots per square inch. A
high-resolution, professional quality laser printer prints at 1200
dpi.
Email List: A way of having a group discussion by electronic mail.
Also used to
distribute announcements to a large number of people. A mailing list
is very much like a conference on a bulletin board system, except
the conversation comes to you in your e-mail box. Each time you or
any member of the list posts a reply to the conversation, it is
distributed to the e-mail box of every member of the list. All of
this
traffic is automated and managed by programs called mailing list
managers (MLM's) or mail servers. The two most frequently used
programs are Listserv and Majordomo.
Mailing lists are the most basic form of Internet conferencing. They
can be public or private and, unlike Usenet newsgroups, which
require additional software to run, all you need to participate is an
e-mail address.
A mailing list is said to be "unmoderated" if all of the messages
sent
to the list are automatically forwarded to each member of the list.
In
a "moderated" list, all messages are sent first to a list moderator,
who makes decisions about which postings will or will not be sent to
everyone on the list.
If many people are on a mailing list, the traffic in your e-mail box
can be overwhelming. One way to deal with this is to subscribe to the
"digest" version of the list (not all mailing lists have digest
versions). In a digest version, postings are collected into a single
file
and distributed to the list on a regular basis (usually daily). In
this
way you receive only one big file at regular intervals rather than
hundreds of small ones everyday.
You join a mailing list by subscribing to it - also termed Opting-In
or Opt-in Direct Email. This doesn't mean you
have to pay money, it just means you are asking to have your e-mail
address added to the distribution list. To get off the mailing list,
you
have to unsubscribe from the list. You do both by sending an e-mail
message to the list administrator with the following in the body of
your message:
subscribe name-of-list your e-mail address
or
unsubscribe name-of-list your e-mail address
The exact way of doing this varies a little from list to list. It's
best to
request information about the list first and that will tell you
exactly
what you need to do. Once you've subscribed to a list you will
receive an e-mail message with details about how the list works and
how to unsubscribe.
Firewall: A combination hardware and software buffer that many
companies
or organizations have in place between their internal networks and
the Internet. A firewall allows only specific kinds of messages from
the Internet to flow in and out of the internal network. This
protects
the internal network from intruders or hackers who might try to use
the Internet to break into those systems.
Flaming: A combination hardware and software buffer that many
companies
or organizations have in place between their internal networks and
the Internet. A firewall allows only specific kinds of messages from
the Internet to flow in and out of the internal network. This
protects
the internal network from intruders or hackers who might try to use
the Internet to break into those systems.
Forms: Forms are web pages comprised of text and "fields" for a
user to fill
in with information. They are an excellent way of collecting and
processing information from people visiting a web site, as well as
allowing them to interact with web pages. Forms are written in
HTML and processed by CGI programs. The output can be sent as
an e-mail form, stored online, printed, and/or returned to the user
as
an HTML page. When you enter a keyword in the search field of an
Internet directory, you are filling in a form. It is then processed
by a
CGI program, returning a list of possible matches with your
keyword. Forms are also used for online catalogs, surveys, requests
for information, and conferencing.
FTP: An acronym for File Transfer Protocol -- a very common method
of
transferring one or more files from one computer to another. FTP is
a specific way to connect to another Internet site to retrieve and
send files. FTP was developed in the early days of the Internet to
copy files from computer to computer. With the advent of the World
Wide Web, and web browser software, you no longer need to know
arcane FTP commands to copy to and from other computers. In your
browser, you can use FTP by typing the URL into the location box at
the top of your screen. For example:
ftp://name.of.site/directory/filename.zip will transfer filename.zip
to
your computer's hard disk. You can also use
ftp://name.of.site/directory/ which will give you a listing of all
the files
available in that directory.
If you are using a web browser that doesn't have built-in FTP
capability, or if you want to upload files to a remote computer, you
will need to use an FTP client program to transfer files. To use FTP
you need to know the name of the file, the computer where it
resides, and the directory it's in. Most files are available via
"anonymous FTP," which means you can log into the machine with
the user name "anonymous" and use your e-mail address as your
password.
GIF or .gif: Acronym for Graphics Interchange Format. This
graphics file
format uses a compression scheme originally developed by
CompuServe. Because they are compressed, the file sizes can be
quickly and easily transmitted over a network. That's why it is the
most commonly used graphics format on the World Wide Web.
Graphical User Interface (GUI): A GUI interface allows users to
navigate and interact with
information on their computer screen by using a mouse to "point,"
"click," and "drag" icons and other data around on the screen,
instead of typing in words and phrases. The Windows and Macintosh
operating systems are examples of GUI's. The World Wide Web is
an example of a GUI designed to enhance navigation of the Internet,
once done exclusively via terminal-based (i.e. typed command line)
functions.
Hit: This term refers to the number of files that are downloaded
from a
web server. It's a way of measuring traffic to a website that can be
misleading. The number of hits a site receives is usually much
greater than the number of visitors it gets. That's because a web
page can contain more than one file. For example, each graphic
element is a separate file, so a page with nine graphics would count
as ten hits, one for each graphic and one for the HTML file. In this
scenario a page may have 10,000 hits, but only 1,000 visits.
HTML: Acronym for HyperText Markup Language, HTML is the computer
language used to create hypertext documents. HTML utilizes a
finite list of tags that describe the general structure of various
kinds
of documents linked together on the World Wide Web.
HTTP: HTTP stands for HyperText Transfer Protocol -- the method by
which hypertext files are transferred across the Internet. Letās
examine these terms one at a time. "Hypertext" was coined by Ted
Nelson in 1965 to mean "text which is not constrained to be linear."
When used with the web, it is text that is linked to something else.
When you click on a word and you are shown another page (or a
sound file or a picture), you are using hypertext. Hypertext allows
you to jump around between files, following your own interests and
train of thought. World Wide Web pages written in HTML use
hypertext to link to other documents.
Hypertext transfer is simply the tranfer of hypertext files from
computer to computer. When you are reading a hypertext document,
say, at the Library of Congress site, you can click on a link that
takes you to the NASA page. Of course, you haven't actually gone
anywhere. A document simply has been transferred from NASA's
computer to your computer, across the Internet.
Now what on earth is protocol? In computerese, a protocol is a set of
standards used by two computers to communicate and exchange
information with each other. To put it all together, HyperText
Transfer Protocol is the set of standards used by computers to
transfer hypertext files (web pages) over the Internet.
Hypertext: A way of presenting information in which text, sounds,
images, and
actions are linked together in a way that allows you to jump around
between them in whatever order you choose. Hypertext usually
refers to any text available on the World Wide Web that contains
links to other documents.
Image Map: An image map is a graphic divided into regions or
"hotspots." When
a particular region is clicked, it calls up a web page that has been
associated with that particular region. A typical example of an image
map is a web site that offers national information organized by
state.
Clicking on a state on a map of the United States calls up the
appropriate page.
Internet Service Provider (ISP): Also called access providers. The
remote computer system
to which you connect your personal computer and through which you
connect to the Internet. ISPs that you access by modem and
telephone line are often called dial-up services.
Intranet: You can think of an intranet as an internal Internet
designed to be
used within the confines of a company, university or organization.
What distinguishes an intranet from the freely accessible Internet,
is
that intranets are private. Until recently most corporations relied
on
proprietary hardware and software systems to network its
computers, a costly and time-consuming process made more difficult
when offices are scattered around the world. Even under the best of
conditions, sharing information among different hardware platforms,
file formats and software is not an easy task. By using off-the-shelf
Internet technology, intranets solve this problem, making internal
communication and collaboration much simpler.
Intranets use TCP/IP to transmit information across the network, as
well as HTML to create documents.Information is stored on one or
more company servers and accessed by using a web browser, such
as Navigator or Explorer. This self-contained, miniature Internet
can have all the same features -- individual home pages,
newsgroups, e-mail - but they are restricted to company employees
and contractors.
IP Address: A numeric code that uniquely identifies a particular
computer on the
Internet. Just as a street address identifies the location of your
home or office, every computer or network on the Internet has a
unique address, too. Internet addresses are assigned to you by an
organization called InterNIC. You register your address with
InterNIC as both a name (whitehouse.gov), which is referred to as
the domain name, and a number (198.137.240.100), which is
generally referred to as the IP address or IP number.
Because the numeric addresses are difficult to understand or
remember, most people use names instead like whitehouse.gov or
ibm.com. A software database program called Domain Name
Service (DNS) tracks the names and translates them into their
numerical equivalent so that the computers can understand what
they are and find them. See Domain Name.
When you have a standard dial-up account with an Internet provider,
you will either be assigned a "permanent" or "static" IP address
(i.e. its always the same), or the system will use "dynamic" IP
addressing, which assigns you an address every time you log on. If
you are an organization and want all of your employees' computers
to have Internet access, you can apply to the InterNIC for a range
of IP addresses. Most likely, the InterNIC will assign you a Class C
address, which consists of 255 unique IP numbers for you to assign
to your employees.
If you need more than 255 IP address, you can apply for a Class B
address, which will give you over 65,000 unique IP addresses. Class
A addresses are for very large companies. Both Class A and Class
B addresses are very hard, if not impossible, to get. Usually,
companies will get multiple Class C addresses. Actually, we're
quickly running out of IP addresses. So the Internet Engineering
Task Force, which standardized the IP protocol, is working on a
solution, described in IP: Next Generation. The document is rather
technical, so beware.
ISDN: An acronym for Integrated Services Digital Network. ISDN
lines are
connections that use ordinary phone lines to transmit digital instead
of analog signals, allowing data to be transmitted at a much faster
rate than with a traditional modem.
ISDN converts audio signals - your voice for instance - into digital
bits. Since bits can be transmitted very quickly, you can get much
faster speed out of the same telephone line - four times faster than
a
14.4 kbps modem. In addition, ISDN connections are made up of two
different channels, allowing two simultaneous "conversations" so
you can speak on one channel and send a fax or connect to the
Internet over another channel. All of these transactions occur on the
same twisted-pair phone line currently plugged into your telephone.
To find out if you can get ISDN, contact your local phone company
or call around to a few local Internet service providers.
ISDN is a powerful tool for Internet communications, but it is not
available everywhere. Traditionally, it has been used in urban
business zones and large corporate settings with special digital
switching equipment, but residential ISDN service is expanding
rapidly. If you are shopping for an Internet access provider that
offers you ISDN, be sure to thoroughly evaluate the equipment
costs. An ISDN line can offer you inexpensive, high-bandwidth
connections, but you may have to buy special equipment (like
routers and switchers) that allow ISDN to communicate with your
internal networks.
Java: Java is an object-oriented programming language developed by
Sun
Microsystems, Inc. to create executable content (i.e self-running
applications) that can be easily distributed through networks like
the
Web. Developers use Java to create special programs called applets
that can be incorporated in a web page to make it interactive. A
Java-enabled web browser like Sun's HotJava is required to
interpret and run the Java applets.
Like a gateway (CGI) script, Java is activated by a special HTML
tag on a web page. But unlike gateway scripts, which require
information that exists on the server to run applications or process
input, Java enables developers to create content that can be
delivered to and run by users on their computers. This software can
support anything that programmers can dream up, from
spreadsheets and tutorials to interactive games and animation.
JPEG: Acronym for Joint Photographic Experts Group, an industry
committee that developed a compression standard for still images.
JPEG refers to the graphics file format that uses this compression
standard. You will find JPEG files on the World Wide Web with the
file extension .JPG.
Link: Generally refers to any highlighted words or phrases in a
hypertext
document that allow you to "jump" to another section of the same
document or to another document on the World Wide Web.
MIME (Multipurpose Internet Mail Extension): MIME stands for
Multipurpose Internet Mail Extension, a standard
system for identifying the type of data contained in a file based on
its extension. MIME is an Internet protocol that allows you to send
binary files across the Internet as attachments to e-mail messages.
This includes graphics, photos, sound and video files, and formatted
text documents. MIME has to negotiate many different operating
systems and types of software to perform this amazing feat. Its
invention has been a major step forward in the exchange of non-text
information over the Internet.
E-mail programs that allow you to send and receive these types of
files are said to be MIME-compliant. Many of these programs now
incorporate MIME and have made it practically invisible to the
user. You are probably using MIME when you send e-mail with an
"attachment" of a formatted file. If not, then your mail program is
using something very similar called UUencoding and UUdecoding to
achieve the same result.
Mirror: An FTP server that provides copies of the same files as
another
server. Used when an FTP site is so popular that the volume of users
accessing it keeps others from getting through. A mirror site
provides an alternate way to access the same files.
Navigation Tools: Navigation tools allow users to find their way
around a website or
multimedia presentation. They can be hypertext links, clickable
buttons, icons, or image maps. Navigation tools are usually present
either at the bottom or top (sometimes both) of each page or screen
and typically allow users to return to the previous page, move
forward to the next page, jump to the top of the current page and
return to the home page.
Netiquette: A form of online etiquette. This term refers to an
informal code of
conduct that governs what is generally considered to be the
acceptable way for users to interact with one another online.
Newsgroups: Electronic discussion groups consisting of collections
of related
postings (also called articles) on a particular topic that are posted
to
a news server which then distributes them to other participating
servers. There are thousands of newsgroups covering a wide range
of subjects. You must subscribe to a newsgroup in order to
participate in it or to track the discussion on an on-going basis.
Unlike with a magazine or newspaper, subscribing to a newsgroup
does not cost anything.
Newsgroups are found primarily on Usenet. Usenet is the collection
of computers that participate in a global conferencing system that
make newsgroups perhaps the largest distributed bulletin board
system in the world. Newsgroups are one of the oldest and most
widely used services on the Internet. There are more than 13,000 of
them, with new ones coming online all the time. Not all newsgroups
are carried by Usenet, and Usenet is carried by networks that are
not on the Internet.
Newsreader: A software program that lets you subscribe to
newsgroups as well as
read and post messages to them. A newsreader is like a friendly
librarian who keeps track of the articles posted to the newsgroups
you like to read and locates them when you want to read them.
Object-oriented Programming: A programming technique that speeds
the development of programs
and makes them easier to maintain through the re-use of "objects"
that have behaviors, characteristics, and relationships associated
with them. The objects are organized into collections (also called
class libraries) which are then available for building and
maintaining
applications. Each object is part of a "class" of objects, which are
united via "inheritance" and share certain characteristics and
relationships.
Packet/Packet Switching: A packet is a chunk of information sent
over a network.
Packet-switching is the process by which a carrier breaks up data
into these chunks or "packets." Each packet contains the address of
origin, the address of its destination, and information about how to
reunite with other related packets. This process allows packets from
many different locations to co-mingle on the same lines and be
sorted and directed to different routes by special machines along the
way.
Page view: Like an ad view but for an individual Web page. A page
view occurs each time a Web page is requested from a server.
Pathname: A pathname indicates the location of a particular file
or directory by
outlining the route or "path" from the host name (if the file resides
on a remote server) through the directory structure to the desired
filename or directory name. Each name in the series of names that
define a path are separated by a slash. If the file is located in the
current working directory on your computer, it is referred to only by
its filename.
Pathnames can be absolute or relative. An absolute pathname
provides the full path (address) of a file, including the computer
system, directories, and subdirectories (if any) it resides in.
Relative
pathnames are used to describe a file or directory location on the
user's system relative to the user's current location on the system
(i.e. based on which level of the directory structure the user is
in).
PERL (Practical Extraction and Reporting Language): A robust
programming language frequently used for creating CGI
programs on web servers because it is faster than UNIX shell script
programs, it can read and write binary files, and it can process very
large files. The major advantage of PERL over C as a programming
language is that PERL does not need to be compiled.
Pixel: A pixel (short for picture element) is the smallest element
that can
be displayed on a video screen or computer monitor, and is often
used as a unit of measurement for image size and resolution. The
number of pixels (width and height) in an image defines its size and
the number of pixels in an inch defines the resolution of the
image.
Plug-in: A plug-in extends the capabilities of a web browser, such
as
Netscape Navigator or Microsoft Explorer, allowing the browser to
run multimedia files. The term "plug-in" is used in two ways on the
Internet. The technical definition of a plug-in is a small add-on
piece
of software that conforms to Netscape Navigator standard. Other
browsers however, including Microsoft Explorer, support many
Netscape plug-ins. But Explorer actually uses a different software
standard, called an ActiveX control, instead of plug-ins.
PPP: PPP (Point-to-Point Protocol) is a communications protocol
used to
transmit network data over telephone lines. It allows you to connect
your computer to the Internet itself, rather than logging on through
an Internet Service Provider's host computer and using UNIX
commands through a shell. This type of connection lets you
communicate directly with other computers on the network using
TCP/IP connections. It is part of the TCP/IP suite of programs
necessary to connect to and use the Internet.
If you have a dial-up account with an Internet service provider, you
are using either PPP or SLIP to make your connection to the
Internet. PPP (Point-to-Point Protocol) is rapidly replacing SLIP
(Serial Line Internet Protocol) as the more common standard.
Where as SLIP is easy to install and to use, it does not provide
error
correction or certain negotiation features that are built into PPP.
Where do you get PPP? If you bought an Internet package, a PPP
program would be part of the collection of software programs you
received. Some Internet Service Providers will give you a disk with
the appropriate software when you sign up for an account. Others
will point you to a BBS where you can download the software
yourself.
Rich-media ads: HTML or JavaScript banner ads that may offer
multiple functions, such as pull-down menus or search fields.
Robots: Programs that are designed to automatically go out and
explore the
Internet for a variety of purposes. Robots that record and index all
of the contents of the network to create searchable databases are
sometimes called Spiders or Worms. WebCrawler and Lycos are
popular examples of this.
Shockwave: Shockwave is a set of programs that allow Macromedia
Director
animation files to be played over the Internet with a web browser.
Possible uses for this type of animation on the Web include online
advertising, games, training, and animated logos.
Signature: Text automatically included at the bottom of an e-mail
message or
newsgroup posting to personalize it. This can be anything from a
clever quote to some additional information about the sender, like
their title, company name and additional e-mail addresses they may
have. Netiquette suggests that signatures be four lines or fewer.
Site traffic: An ambiguous term. Some consider the number of unique
visitors during a given period to be a site's traffic. Others consider it
the number of page views during a given period (usually a month).
SLIP: An acronym for Serial Line Internet Protocol. SLIP is a
communications protocol that, like PPP, allows you to connect your
computer to the Internet itself, using a telephone line. It is part
of
the TCP/IP suite of programs necessary to connect to and use the
Internet.
If you have a dial-up account to an Internet service provider, you
are using either PPP or SLIP to make your connection to the
Internet. Although SLIP is easy to install and use, it does not
provide the error correction or negotiation features that PPP has.
For this reason, PPP is rapidly replacing SLIP as the more common
Standard.
SPAM: Originally just a canned sandwich filler product, now this
term is also
used to refer to the practice of blindly posting commercial messages
or advertisements to a large number of unrelated and uninterested
newsgroups.
Secure Socket Layer (SSL):
A protocol developed by Netscape Communications Corporation for
securing data transmission in commercial transactions on the
Internet. Using public-key cryptography, SSL provides server
authentication, data encryption, and data integrity for client/server
communications.
T-1 Line: A high-speed digital connection capable of transmitting
data at a
rate of approximately 1.5 million bits per second. A T1 line is
typically used by small and medium-sized companies with heavy
network traffic. It is large enough to send and receive very large
text files, graphics, sounds, and databases instantaneously, and is
the fastest speed commonly used to connect networks to the
Internet. Sometimes referred to as a leased line, a T1 is basically
too large and too expensive for individual home use.
T-3 Line: A super high-speed connection capable of transmitting
data at a rate
of 45 million bits per second. This represents a bandwidth equal to
about 672 regular voice-grade telephone lines, which is wide enough
to transmit full-motion real-time video, and very large databases
over a busy network. A T3 line is typically installed as a major
networking artery for large corporations and universities with high
volume network traffic. For example, the backbones of the major
Internet service providers are comprised of T3 lines.
TCP/IP: Stands for Transmission Control Protocol/Internet
Protocol. This is
the language governing communications between all computers on
the Internet. TCP/IP is a set of instructions that dictates how
packets of information are sent across multiple networks. Also
included is a built-in error-checking capability to ensure that data
packets arrive at their final destination in the proper order.
IP, or Internet Protocol, is the specification that determines where
packets are routed to, based on their destination address. TCP, or
Transmission Control Protocol, makes sure that the packets arrive
correctly at their destination address. If TCP determines that a
packet was not received, it will try to resend the packet until it is
received properly.
Telnet: A software program that allows you to log in to other
remote
computers on the Internet to which you have access. Once you are
logged into the remote system, you can download files, engage in
conferencing, and perform the same commands as if you were
directly connected by computer. You need an Internet account to be
able to use a telnet program.
Unique users: The number of different users who access a Web site
or page during a given period. To measure this, Web sites often
employ a user registration system.
UNIX: UNIX is the trademarked name of the multi-user,
multi-tasking,
time-sharing operating system developed at AT&Tās Bell Labs in
1969. Many web sites are maintained on UNIX systems. While
technically the name UNIX refers to only a few trademark-licensed
versions, it is often used to refer to the many versions currently
available on the market. The differences to the user are slight.
UNIX was originally designed on a "spare" minicomputer, to allow
some folks to have a quick time-sharing system to simplify their
documentation procedures. The moniker UNIX was given to it by
the somewhat sarcastic users of the huge mainframes prevalent in
those days -- pointing out that they considered it to be a somewhat
underpowered operating system.
AT&T commercially released UNIX in the early 1970ās. By the late
'70s, the University of California, Berkeley had developed its own
version, called BSD (for Berkeley Software Distribution), which it
offered for free to other colleges and universities
Because it could run on many different computer platforms, it
quickly became the platform of choice for many researchers and
students. Since networking and e-mail are both integral to UNIX, it
was easy for two or more UNIX computers to "talk" to each other.
That is why by the late 1980ās, UNIX ran on almost every machine
on the Internet. In fact, the Internet's protocols were developed on
UNIX machines, for UNIX machines. For example, Usenet, the
loose confederation of computers that exchanges newsgroups and
electronic mail by passing messages back and forth, was based
almost exclusively on UNIX machines.
UNIX now runs on every hardware platform from PC and Macintosh
to high- performance graphical workstations to multimillion dollar
supercomputers. The big difference between versions and platforms
is that the more expensive platforms run faster or support more
simultaneous users.
URL (Uniform Resource Locator): An acronym for Uniform Resource
Locator. URL is the address for
a resource or site (usually a directory or file) on the World Wide
Web and the convention that web browsers use for locating files and
other remote services.
Usenet: Usenet refers to the collection of newsgroups (sometimes
called the
Big Eight hierarchies) and a set of agreed-upon rules for
distributing
and maintaining them. More than 13,000 newsgroups exist around
the world and the majority of them are a part of Usenet. However, a
fairly large number of alternative newsgroups have emerged outside
of Usenet.
Usenet newsgroups are arranged hierarchically first by the name of
the group, followed by the name of the subgroups. Each name in the
hierarchy is separated by a period. For example, the discussion
group about rose gardening is rec.gardens.roses. This means the
conversation is in the general grouping of rec. (which stands for
recreation), and a subgroup of recreation called gardens. In this
particular case, an additional subgroup of gardens has been created
for roses. Each additional subgroup in a hierarchy defines how
narrow or specialized the discussion topic is. It's not uncommon to
find newsgroups with several subgroups.
The Usenet Big Eight hierarchies are:
comp - computer science and related topics
news - information about the newsgroups
rec - hobbies and recreational activities
sci - scientific research and applications
soc - social issues, including politics
talk - debate on controversial topics
misc - anything that doesn't fit in the above categories
Not all newsgroups are part of Usenet. For example, the newsgroups
with a prefix of alt. are not part of the core Usenet newsgroups,
although they may look just like Usenet newsgroups to the average
user. Another example of a non-Usenet newsgroup is the Clarinet
news feed, which is a commercial information service that also looks
like any other newsgroup to the end-user.
System administrators decide which newsgroups will be carried on
their systems. Making newsgroups available to their users means
dedicating hard-drive space for storage, so decisions have to be
made about the allocation of those resources. Many administrators
will not carry the "alt." groups. Some even refuse to carry any
group with the word "sex" in the name. You have to check with your
provider to find out what newsgroups they carry.
Visitor: An individual who interacts with a Web site. Several
methods
are being used to identify visitors.
Visits: A series of page requests by a visitor on a given site
within a
specified period, usually 30 minutes. Visits usually break down into the
number of pages requested per visit per unique user. That way you
know who visits your site, how often they come and how long they
stay.
VRML (Virtual Reality Modeling Language): VRML is an open,
platform-independent file format for 3-D graphics
on the Web. It encodes computer-generated graphics in a way that
makes them easily transported across the network. VRML requires
a special web browser to display these graphics which simulate
virtual reality 3-D "environments" or "worlds" through which the
user can move and interact with objects. These 3-D "worlds" can
contain objects that link to documents, other objects, or other 3-D
worlds.
Webmaster: A person in charge of maintaining a web site. This can
include
writing HTML files, setting up more complex programs, and
responding to e-mail. Many sites encourage you to mail comments
and questions about the site's web pages to the web master.
Web Page: A web page is a document created with HTML (HyperText
Markup
Language) that is part of a group of hypertext documents or
resources available on the World Wide Web. Collectively, these
documents and resources form what is known as a web site.
You can read HTML documents that reside somewhere on the
Internet or on your local hard drive with a piece of software called
a
web browser. Web browsers read HTML documents and display
them as formatted presentations, with any associated graphics,
sound, and video, on a computer screen.
Web pages can contain hypertext links to other places within the
same document, to other documents at the same web site, or to
documents at other web sites. They also can contain fill-in forms,
photos, large clickable images (image maps), sounds, and videos for
downloading.
Web Site: The collection of network services, primarily HTML
documents,
that are linked together and that exist on the Web at a particular
server. Exploring a web site usually begins with the home page,
which may lead you to more information about that site. A single
server may support multiple web sites.
World Wide Web: The exact definition for the World Wide Web
(popularly known as
the Web) varies, depending on whom you ask. Three common
descriptions are:
- 1.A collection of resources (Gopher, FTP, http, telnet,
Usenet,
WAIS and others) which can be accessed via a web browser.
- 2.A collection of hypertext files available on web
servers.
- 3.A set of specifications (protocols) that allows the
transmission
of web pages over the Internet.
You can think of the Web as a worldwide collection of text and
multimedia files and other network services interconnected via a
system of hypertext documents. HTTP (HyperText Transfer
Protocol) was created in 1990, at CERN, the European Particle
Physics Laboratory in Geneva, Switzerland, as a means for sharing
scientific data internationally, instantly, and inexpensively. With
hypertext a word or phrase can contain a link to other text. To
achieve this they developed a programming language called HTML,
that allows you to easily link you to other pages or network services
on the Web.
If you encounter a page with a word that is highlighted in some way
(usually in a different color and underlined), you can click on that
word and "go to" the page or resource to which connects. Of course,
you are not actually "going" anywhere when you do this, but rather,
you are summoning the file or resource that the link points to. This
non-linear, non-hierarchical method of accessing information was a
breakthrough in information sharing and quickly became the major
source of traffic on the Internet.
The basic elements of the World Wide Web are:
- HTTP (Hypertext Transfer Protocol) - the set of standards
used by computers to communicate and share files with each
other.
- URL's (Uniform Resource Locator) - the "address" of a
resource (file or diretory) on the Web.
- HTML (Hypertext Markup Language) - the programming
"tags" added to text documents that turn them into hypertext
documents.
The World Wide Web Consortium at CERN continues to be the
premier source of information about the Web. For more background
information link to the history of CERN involvement in the Web and
the Internet.
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