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Search Engines

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Search Engines are specialized programs that facilitate the retrieval of data from the Internet, on a business related network or on a personal computer system. They allow users to ask for contents meeting certain criteria usually involving a certain word or phrase, then gives a list of articles that matches those words or phrases. There are number of different engines that can be used for different types of searches and can be narrowed for optimal results.

Before the 1990ÐŽ¦s Search Engines were non existent. The first tool to be used for searching the Internet was Archie, which was created in 1990 by a student named Alan Emtage who attended McGill University in Motreal. Searches were achieved by downloading director listing of files on public FTP (File Transfer Protocol) sites. This created a database of files for searching but could not search by file contents.

The first Web search engine was Wandex that was created by Matthew Gray at MIT in 1993, this no longer in exists. Another earlier search engine Aliweb created in 1933 still exists today. The first full text and widely know search engine was WebCrawler which was introduced 1994. Unlike previous search engines WebCrawler became the standard for all future search engines. It gave its users the option to search for any word on any webpage. Since then numerous search engines have became accessible on the Internet. The most popular with total market share and number of searches for April 2007 were:

Source: Nielsen/NetRatings, 2007

Search Engines # Of Searches April 2007 Market Share April 2007

Google 3,773,032 55.2

Yahoo 1,497,154 21.9

MSN/Windows Live 612,526 9.0

AOL 371,038 5.4

Ask.com 126,286 1.8

My Web Search 67,958 1.0

Comcast 35,239 0.5

Earthlink 30,022 0.4

Dogpile.com 28,556 0.4

My Way 26,814 0.4

Other 269,069 3.9

Total Searches 6,837693 100.00

The majority of search engines are free of charge to their users. However, there are some fee-based search services that are provided by some of these engines. Search engines such as Google has launched its Premier Edition ÐŽ§Google AppsЎЁ which offers all the features of standard Google in addition to 99.9% uptime guarantee for email, 10 GB/account, ability to turn off ads, shared calendar resources, limited email migration tools, 24/7 assistance with phone support, 3rd party applications and service, APIs to integrate with your existing infrastructure, single sign-on, user provisioning and management, and support for email gateway. Yahoo has also joined the fee-based provider by forming collaboration with news providers such as Dow Jones, The Wall Street Journal Online, and research providers such as Forrester Research. These search engines along with others that offer such service requires a subscription signup. Search Engines provide numerous benefits to their users, however due to the rate at which the Internet is growing, major search engines have become slow at indexing new webpages. Other problems faced by search engines are the fact that webpages are updated daily and forces search engines to revisit them periodically; queries are limited to looking for key words and can produce irrelevant results, to narrow searches it would prove feasible to use proximity-search option with search-bracket to limit the matches in a paragraph or phrase; sites that are vigorously generated may take time or is difficult to index, or they may result in numerous results; Some of these vigorously generated sites are not indexable by search engines at all; it is sometimes difficult getting exactly what you are looking for; money is also a big factor in terms of relevance of information, the more money a website pays the more relevant their information will be; websites have come up with different ways to manipulate search engines to display their sites in higher results, this causes some search results to be filled with linkspam or bait-and-switch pages; and finally crawlers are hindered by secure websites, either they are unable to browse the content of the website for technical reason or wonÐŽ¦t index it for privacy reasons.

There are three types of search engines: some that are powered by robots (called crawlers; ants or spiders), some that are powered by human submissions; and some that are a hybrid of the two. Crawlers search engines are automated software agents that go to individual websites and read the information there, they also read the sites meta tags and trace links that are connected to that site. Human-powered search engines depend on the human element to enter information which is then indexed and catalogued.

Performing a query on a search engine is actually searching through that engines index that it created. Because these indices are giant databases of information that is collected, stored, and then searched, sometimes engines like Yahoo and Google will return dead links results. If a webpage becomes invalid because the index is not updated, the search engines still treat this web page as active until the links are updated. Search engines such as Google stores all or some of its cache (source page) and information about the web pages. On the other hand Alta Vista stores every word of every page they find. Because all indices are not the same and not all search engines uses the same algorithm (what engines uses to priorities information), the same search on different engines will produce different results. These algorithms scan for frequency and location of keywords on a Web page, the words with higher frequency is considered more relevant. Search engines are becoming more and more sophisticate with technologies to eliminate this type of occurrence known as keyword stuffing or spamdexing, and also deter Web masters who create artificial links on their sites to boost artificial ranking. Algorithm plays an important role in the linking of different web pages. They analyze these linked pages and enable the search engine to determine whether the page is important and deserving of a boost in rankings.

In an attempt at narrowing queries most search engines has implemented the use of Boolean operators AND, OR and NOT. Some engines also provide a feature called proximity search that gives users the ability to define the distance between keywords. Search engines can be useful resource tools depending on the results

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