The Internet is a
world-wide communication matrix that provides users with access to
electronic mail, news, training and instruction, maps, computer files,
games, and countless volumes of information on virtually any subject.
The Internet even links customers to commercial Web sites, where one
can compare and buy products without ever leaving home.
Information is transmitted
over the network in small chunks, called packets, that are sent over
multiple paths to a single destination, where they are reassembled in
the proper sequence. If one portion of the network is disabled,
packets are simply routed through a different portion of the network.
This makes the system extremely reliable and flexible.
The
matrix connects computers all over the world where information is
stored and made available to the system. These are called
"servers" because they "serve" the information up
to the system. Of all the information available on these servers, only
some 17% is indexed and searchable. The rest makes up what is
referred to as the "hidden internet".
Software
known as a "search engine" is used to index and
report on the available information. Some of the more widely known and
used engines include AOL, Google, and AltaVista.
Directories
are also loosely referred to as search engines, even though they
differ in how they operate. The best known directory is Yahoo.
Directories now supplement their listings through the use of search
engines. The feature that distinguishes a search engine from a
directory is that it utilizes "spiders", or
"crawlers", or "bots". These are software
tools that roam around the net gathering information and storing it in
databases for the search engines.