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Generally, there are three
types of search engines:
computer-generated indexes,
directories and meta search
engines.
More commonly referred to as
crawlers or web spiders,
computer-generated indexes like
WebCrawler scan the Internet
looking for words relevant to
your search. Directories like
Yahoo are lists of sites edited
by human beings and organized by
topic matter. Many sites are a
combination of both.
The third category includes meta
search engines, which search
other engines for you.
MetaCrawler and Dogpile are meta
engine examples. Ask is a meta
engine that allows users to enter
queries in the form of a
question. Ask
Jeeves For Kids gives kids
access to a screened
metasearch.
The first tool for searching the
Internet, created in 1990, was
called "Archie". It downloaded
directory listings of all files
located on public anonymous FTP
servers; creating a searchable
database of filenames. A year
later "Gopher" was created. It
indexed plain text documents.
"Veronica" and "Jughead" came
along to search Gopher's index
systems. The first actual Web
search engine was developed by
Matthew Gray in 1993 and was
called "Wandex".
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