Wikipedia:Google Test

A search engine lists web pages on the Internet. This facilitates research by offering an immediate variety of applicable options. Possibly useful items on the results list include the source material or the electronic tools that a web site can provide, such as a dictionary, but the list itself, as a whole, can also indicate important information. However, discerning that information may require insight.

The advantages of a specific search engine can be distinguished by using a variety of common search engines. The distinct advantages of each are their user interface and, less obviously, their algorithms for compiling and searching their own indexes. Because a web crawler can be blocked—specific ones or just in general—different search engines can list different web sites, and there are more web sites available by URL than are indexed in any database.

The most common search engines are at Google, Bing, and Yahoo. Specialized search engines exist for medicine, science, news and law amongst others. Several generalized search engines exist. These adapt your query to many search engines. See Common search engines below. This page mostly uses Google instead of Bing or Yahoo, but aims for generality where it can. For example, it describes Google Groups (usenet groups), Google scholar (academia), Google news, and Google books.

If an unsourced addition to an article appears plausible, consider taking a moment to use Google (or some other search engine) to find a reliable source before deciding whether to revert.

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