A web search engine is a software system that is designed to search for information on the World Wide Web. The search results are generally presented in a line of results often referred to as search engine results pages (SERPs). The information may be a mix of web pages, images, and other types of files. Some search engines also mine data available in databases or open directories. Unlike web directories, which are maintained only by human editors, search engines also maintain real-time information by running an algorithm on a web crawler.
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Google is the world's most popular search engine, with a marketshare of 68.69 per cent.[15] Baidu comes in a distant second, answering 17.17 per cent online queries.[15]
The world's most popular search engines are:[15]
| Search engine | Market share in June 2014 | |
|---|---|---|
| 68.69% | ||
| Baidu | 17.17% | |
| Yahoo! | 6.74% | |
| Bing | 6.22% | |
| Excite | 0.22% | |
| Ask | 0.13% | |
| AOL | 0.13% | |
Customized results and filter bubbles[edit]
Many search engines such as Google and Bing provide customized results based on the user's activity history. This leads to an effect that has been called a filter bubble. The term describes a phenomenon in which websites use algorithms to selectively guess what information a user would like to see, based on information about the user (such as location, past click behaviour and search history). As a result, websites tend to show only information that agrees with the user's past viewpoint, effectively isolating the user in a bubble that tends to exclude contrary information. Prime examples are Google's personalized search results and Facebook's personalized news stream. According to Eli Pariser, who coined the term, users get less exposure to conflicting viewpoints and are isolated intellectually in their own informational bubble. Pariser related an example in which one user searched Google for "BP" and got investment news about British Petroleum while another searcher got information about the Deepwater Horizon oil spill and that the two search results pages were "strikingly different".[24][25][26] The bubble effect may have negative implications for civic discourse, according to Pariser.[27]
Since this problem has been identified, competing search engines have emerged that seek to avoid this problem by not tracking[28] or "bubbling"[29] users.
| Timeline (full list) | ||
|---|---|---|
| Year | Engine | Current status |
| 1993 | W3Catalog | Inactive |
| Aliweb | Inactive | |
| JumpStation | Inactive | |
| 1994 | WebCrawler | Active, Aggregator |
| Go.com | Active, Yahoo Search | |
| Lycos | Active | |
| Infoseek | Inactive | |
| 1995 | AltaVista | Inactive, redirected to Yahoo! |
| Daum | Active | |
| Magellan | Inactive | |
| Excite | Active | |
| SAPO | Active | |
| Yahoo! 2008 | Active, Launched as a directory | |
| 1996 | Dogpile | Active, Aggregator |
| Inktomi | Inactive, acquired by Yahoo! | |
| HotBot | Active (lycos.com) | |
| Ask Jeeves | Active (rebranded ask.com) | |
| 1997 | Northern Light | Inactive |
| Yandex | Active | |
| 1998 | Active | |
| MSN Search | Active as Bing | |
| empas | Inactive (merged with NATE) | |
| 1999 | AlltheWeb | Inactive (URL redirected to Yahoo!) |
| GenieKnows | Active, rebranded Yellowee.com | |
| Naver | Active | |
| Teoma | Active | |
| Vivisimo | Inactive | |
| 2000 | Baidu | Active |
| Exalead | Active | |
| Gigablast | Active | |
| 2003 | Info.com | Active |
| Scroogle | Inactive | |
| 2004 | Yahoo! Search | Active, Launched own web search (see Yahoo! Directory, 1995) |
| A9.com | Inactive | |
| Sogou | Active | |
| 2005 | AOL Search | Active |
| GoodSearch | Active | |
| SearchMe | Inactive | |
| 2006 | wikiseek | Inactive |
| Quaero | Active | |
| Ask.com | Active | |
| Live Search | Active as Bing, Launched as rebranded MSN Search | |
| ChaCha | Active | |
| Guruji.com | Active as BeeMP3.com | |
| 2007 | wikiseek | Inactive |
| Sproose | Inactive | |
| Wikia Search | Inactive | |
| Blackle.com | Active, Google Search | |
| 2008 | Powerset | Inactive (redirects to Bing) |
| Picollator | Inactive | |
| Viewzi | Inactive | |
| Boogami | Inactive | |
| LeapFish | Inactive | |
| Forestle | Inactive (redirects to Ecosia) | |
| DuckDuckGo | Active | |
| 2009 | Bing | Active, Launched as rebranded Live Search |
| Yebol | Inactive | |
| Mugurdy | Inactive due to a lack of funding | |
| Scout (Goby) | Active | |
| NATE | Active | |
| 2010 | Blekko | Active |
| Cuil | Inactive | |
| Yandex | Active, Launched global (English) search | |
| 2011 | YaCy | Active, P2P web search engine |
| 2012 | Volunia | Inactive |
| Cloud Kite | Active, formerly Open Drive cloud search | |
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