Google

Google Search, commonly referred to as Google Web Search or just Google, is a web search engine owned by Google Inc. It is the most-used search engine on the World Wide Web,[4] handling more than three billion searches each day.[5][6]

The order of search on Google’s search-results pages is based, in part, on a priority rank called a “PageRank“. Google Search provides many different options for customized search, using Boolean operators such as: exclusion (“-xx”), alternatives (“xx OR yy OR zz”), and wildcards (“Winston * Churchill” returns “Winston Churchill”, “Winston Spencer Churchill”, etc.)[7] The same and other options can be specified in a different way on an Advanced Search page.

Analysis of the frequency of search terms may indicate economic, social and health trends.[12] Data about the frequency of use of search terms on Google have been shown to correlate with flu outbreaks and unemployment levels, and provide the information faster than traditional reporting methods and surveys.