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.) The same and other options can be specified in a different way on an Advanced Search page.
The main purpose of Google Search is to hunt for text in publicly accessible documents offered by web servers, as opposed to other data, such as images or data contained in databases. It was originally developed by Larry Page and Sergey Brin in 1997. Google Search provides several features beyond searching for words.These include synonyms, weather forecasts, time zones, stock quotes, maps, earthquake data, movie showtimes, airports, home listings, and sports scores. There are special features for numbers, dates, and some specific forms, including ranges, prices, temperatures, money and measurement unit conversions, calculations, package tracking, patents, area codes, and language translation. In June 2011 Google introduced "Google Voice Search" to search for a spoken, rather than typed, words. In May 2012 Google introduced a Knowledge Graph semantic search feature in the US
