A search engine is a program designed to help find information stored on a computer system such as the World Wide Web, or a personal computer. The search engine allows one to ask for content meeting specific criteria (typically those containing a given word or phrase) and retrieving a list of references that match those criteria. Search engines use regularly updated indexes to operate quickly and efficiently.
Without further qualification, search engine usually refers to a Web search engine, which searches for information on the public Web. Other kinds of search engine are enterprise search engines, which search on intranets and personal search engines, which search individual personal computers.
Some search engines also mine data available in newsgroups, large databases, or open directories like DMOZ.org. Unlike Web directories, which are maintained by human editors, search engines operate algorithmically.
The first Web search engine was "Wandex", a now-defunct index collected by the World Wide Web Wanderer, a web crawler developed by Matthew Gray at MIT in 1993. Another very early search engine, Aliweb, also appeared in 1993 and still runs today. One of the first engines to later become a major commercial endeavor was Lycos, which started at Carnegie Mellon University as a research project in 1994.
Soon after, many search engines appeared and vied for popularity. These included WebCrawler, Hotbot, Excite, Infoseek, Inktomi, Open Text, Northern Light, and AltaVista. In some ways they competed with popular directories such as Yahoo!. Later, the directories integrated or added on search engine technology for greater functionality.
In 2002, Yahoo! acquired Inktomi and in 2003, Yahoo! acquired Overture, which owned AlltheWeb and Altavista. In 2004, Yahoo! launched its own search engine based on the combined technologies of its acquisitions and providing a service that gave pre-eminence to the Web search engine over the directory.
Search engines were also known as some of the brightest stars in the Internet investing frenzy that occurred in the late 1990s. Several companies entered the market spectacularly, recording record gains during their initial public offerings. Some have taken down their public search engine, and are marketing Enterprise-only editions, such as Northern Light which used to be part of the 8 or 9 early search engines after Lycos came out.
Before the advent of the Web, there were search engines for other protocols or uses, such as the Archie search engine for anonymous FTP sites and the Veronica search engine for the Gopher protocol.
|
|
| Around 2001, the Google search engine
rose to prominence. Its success was based in part on the
concept of link popularity and PageRank. How many other web sites
and web pages link to a given page is taken into consideration with
PageRank, on the premise that good or desirable pages are linked
to more than others.
SEO began in the mid-1990s, as the first search engines
were cataloging the early Web. Many site owners quickly
learned to appreciate the value of a new listing in a search engine,
as they observed sharp spikes in traffic to their sites. |