Search Engine

I

Introduction

Search Engine, software program that helps users find information stored on a personal computer, or a network of computers, such as the Internet. A user enters search terms, typically by typing a keyword or phrase, and the search engine retrieves a list of World Wide Web (WWW) sites, personal computer files, or documents, either by scanning the content stored on the computers or computer networks being searched or by parsing (analyzing) an index of their stored data.

Search engines are most often used to find pages, files, news, images, and other data on the Web. Some of the most popular Web search engines include Google Inc., Microsoft Network (MSN) Search, and Yahoo! Inc. Each can be accessed from any Web browser, and each can be used for free. (Encarta Encyclopedia is published by the Microsoft Corporation.)

These engines operate by building—and regularly updating—an enormous index of Web pages and files. This is done with the help of a Web crawler, or spider, a kind of automated browser that perpetually trolls the Web, retrieving each page it finds. Pages are then indexed according to the words they contain, with special treatment given to words in titles and other headers. When a user inputs a query, the search engine then scans the index and retrieves a list of pages that seem to best fit what the user is looking for. Search engines often return results in fractions of a second.

Generally, when an engine displays a list of results, pages are ranked according to how many other sites link to those pages. The assumption is that the more useful a site is, the more often other sites will send users to it. Google pioneered this technique in the late 1990s with a technology called PageRank. But this is not the only way of ranking results. Dozens of other criteria are used, and these will vary from engine to engine.

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Many times, search results will also include what are called sponsored links, links that are ranked high in the search results or are prominently displayed because third-party companies pay a fee to the search engine. More often than not, sponsored links are labeled as such, but inexperienced Internet users often have trouble distinguishing between sponsored pages and unsponsored results. Sponsored links provide search engines with their primary source of revenue.

II

Search Engine Controversies

As the 21st century began, controversy erupted over the issue of search engine censorship. In late 2005 and early 2006, Cisco Systems, Inc., Google, MSN, and Yahoo! came under fire for cooperating with the Chinese government in censoring Internet content or providing assistance to trace political dissidents who used the Internet in China. Reporters Without Borders, a France-based organization that promotes freedom of the press, accused Yahoo! of helping the Chinese government identify two dissidents through their Yahoo! e-mail accounts. One dissident, who posted essays on the Internet discussing political corruption in China, was sentenced to eight years in prison for “inciting subversion.” Another, who had used a Yahoo! e-mail to send information about the Tiananmen Square protest, was sentenced to ten years in prison.

In February 2006 a congressional committee, the House Subcommittee on Africa, Global Human Rights and International Operations, heard testimony on the issue. The subcommittee heard reports that Google’s search engine in China filtered out certain search terms, such as human rights and Tiananmen, and that MSN had shut down a Chinese citizen’s blog at the request of the government and disallowed blogs on its MSN Spaces servicing China that contained terms forbidden by the Chinese government. Cisco Systems was criticized for providing hardware used to filter, or censor, Internet information. All four companies defended their practices by saying they were forced to abide with Chinese laws. Company representatives also stated their belief that it was the role of government, not business, to promote democracy and human rights in China. Google’s representative said the company found it an unsatisfactory compromise to create Google.cn but decided it could make a “meaningful, though imperfect, contribution to the overall expansion of access to information in China.” The chair of the House subcommittee, Representative Christopher H. Smith, a Republican of New Jersey, said he would introduce legislation called the Global Online Freedom Act to restrict an Internet company’s ability to censor information regardless of another country’s laws.

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