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Glossary
of Web Definitions
a-b
| c-d | e-f | g-h
| i-j | k-l | m-n | o-p
| q-r | s-t | u-v
| w-x | y-z
Applets
A program designed to be executed from within
another application. Unlike an application, applets cannot be
executed directly from the operating system. Web browsers, which are often equipped with
Java virtual machines, can interpret applets from Web servers.
Because applets are small in files size, cross-platform compatible,
and highly secure (can't be used to access users' hard drives), they
are ideal for small Internet applications accessible from a browser.
Animated
GIF
A type of
GIF
image that can be animated by combining several images into a single
GIF file. GIF animation doesn't give the same level
of control and flexibility as other animation formats but it has
become extremely popular because it is supported by nearly all Web
browsers. In addition, animated GIF files tend to be quite a bit
smaller that other animation files, such as Java
applets
Bandwidth
The
amount of data that can be transmitted in a fixed amount of time.
For digital devices, the bandwidth is usually expressed in bits per
second(bps) or bytes per second.
Bit
Map
A representation, consisting of rows and
columns of dots, of a graphics image in computer memory. The value
of each dot (whether it is filled in or not) is stored in one or
more bits of data. For simple monochrome images, one bit is
sufficient to represent each dot, but for colors and shades of gray,
each dot requires more than one bit of data. The more bits used to
represent a dot, the more colors and shades of gray that can be
represented.
Data
Compression
Storing data in a format that requires less space
than usual. Data compression is particularly useful in
communications because it enables devices to transmit the same
amount of data in fewer bits. Certain types of data, such as bit-mapped
graphics, can be compressed to a small fraction of their normal
size.
Domain
Name
A name that identifies one or more
IP
addresses. For example, the domain name microsoft.com represents
about a dozen IP addresses. Domain names are used in URLs
to identify particular Web
pages.
For example, in the URL
http://www.uhv.edu/index.html,
the domain name is uhv.edu.
There are only a limited number of such
domains. For example:
Flash
A
bandwidth
friendly and browser
independent vector-graphic animation technology. As long as
different browsers are equipped with the necessary plug-ins,
Flash animations will look the same. With Flash, users can draw
their own animations or import other vector-based images.
Forms
A
formatted document containing blank fields that users can fill in
with data. Electronic forms are especially common on the World
Wide Web because the HTML language has
built-in codes for displaying form elements such as text fields and
check boxes. Typically, the data entered into a Web-based form is
processed by a CGI program.
GIF
Pronounced jiff or giff (hard g)
stands for graphics interchange format,
a bit-mapped
graphics file format used by the World
Wide Web. GIF supports color and various resolutions.
It also includes data
compression, but because it is limited to 256 colors, it is more
effective for scanned images such as illustrations rather than color
photos
Hot
Spot
An area of a graphics object, or a section of
text, that activates a function when selected. Hot spots are
particularly common in multimedia applications, where selecting a
hot spot can make the application display a picture, run a video, or
open a new window of information.
HTML
Short
for HyperText Markup Language,
the authoring language used to create documents on the World
Wide Web. HTML defines the structure and layout of a Web
document by using a variety of tags
and attributes. All the
information you'd like to include in your Web page fits in between
the and tags. There are hundreds of other tags used to
format and layout the information in a Web page. Tags are also used
to specify hypertext links. These allow Web developers to direct
users to other Web pages with only a click of the mouse on either an
image or word(s).
Hyperlink
An
element in an electronic document that links to another place in the
same document or to an entirely different document. Typically, you
click on the hyperlink to follow the link. Hyperlinks are the most
essential ingredient of all hypertext systems, including the World
Wide Web.
Image
Map
A
single graphic image containing more than one hot
spot. For example, imagine a graphic of a bowl of fruit. When
you click on a banana, the system displays the number of calories in
a banana and when you click on an apple, it displays the number of
calories in an apple.
JAVA
Java
is a general purpose programming language with a number of features
that make the language well suited for use on the World Wide Web.
Small Java applications are called Java applets
and can be downloaded
from a Web
server and run on your computer by a Java-compatible Web
browser, such as Netscape Navigator or Microsoft Internet
Explorer.
JPEG
Short for Joint Photographic Experts Group,
and pronounced jay-peg. JPEG is a lossy compression technique
for color images. Although it can reduce files sizes to about 5% of
their normal size, some detail is lost in the compression.
Plug-In
A
hardware or software module that adds a specific feature or service
to a larger system. For example, there are number of plug-ins for
your web browser
that enable it to display different types of audio or video
messages.
Resolution
For
graphics monitors, the screen
resolution signifies the number of dots (pixels) on the entire
screen. For example, a 640-by-480 pixel screen is capable of
displaying 640 distinct dots on each of 480 lines, or about 300,000
pixels. This translates into different dpi measurements depending on
the size of the screen. For example, a 15-inch VGA monitor (640x480)
displays about 50 dots per inch.
Script
A script is a list of commands that can be
executed without user interaction. A script language is a
simple programming language with which you can write scripts.
Tag
A command inserted in a document that specifies
how the document, or a portion of the document, should be formatted.
Tags are used by all format specifications that store documents as
text files.
To mark a section of a document with a formatting
command.
URL
Abbreviation of Uniform Resource
Locator, the global address of documents and other
resources on the World
Wide Web. The first part of the address indicates what
protocol to use, and the second part specifies the IP address or the
domain
name where the resource is located.
Web
Browser
A software application used to locate and
display Web pages. The two most popular browsers are Netscape
Navigator and Microsoft Internet Explorer. Both of these are graphical
browsers, which means that they can display graphics as well as
text. In addition, most modern browsers can present multimedia
information, including sound and video, though they require plug-ins
for some formats.
Web
Page
A document on the
World
Wide Web. Every Web page is identified by a unique URL
(Uniform Resource Locator).
Web
Server
A computer that delivers (serves up)
Web
pages. Every Web server has an IP
address and possibly a domain
name. For example, if you enter the URL http://www.uhv.edu/index.html in your
browser,
this sends a request to the server whose domain name is uhv.edu.
The server then fetches the page named index.html and sends
it to your browser. Any computer can be turned into a Web server
by installing server software and connecting the machine to the Internet.
World Wide
Web
A system of Internet
servers
that support specially formatted documents. The documents are
formatted in a script
called HTML
(HyperText Markup Language) that supports links to other
documents, as well as graphics, audio, and video files. This means
you can jump from one document to another simply by clicking on hot
spots. Not all Internet servers are part of the World Wide Web. There are several applications called Web
browsers that make it easy to access the World Wide Web.
W3C
Short
for World Wide Web Consortium, an international consortium of
companies involved with the Internet and the Web.
The organization's purpose is to develop open standards so that the
Web evolves in a single direction rather than being splintered among
competing factions.
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