Google Search (or Google Web Search) is a web search engine owned by Google Inc. Google Search is the most-used search engine on the World Wide Web, receiving several hundred million queries each day through its various services.
The order of search results on Google's search-results pages is based, in part, on a priority rank called a "PageRank". Google Search provides many options for customized search.
The main purpose of Google Search is to hunt for text in publicly accessible documents offered by web servers (in formats such as HTML, PDF, etc.), as opposed to other data, such as with Google Image Search. Google Search was originally developed by Larry Page and Sergey Brin in 1997. Google Search provides at least 22 special features beyond the original word-search capability. 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 dates, including ranges, prices, temperatures, money/unit conversions, calculations, package tracking, patents, area codes and language translation of displayed pages. In June 2011, Google introduced "Google Voice Search" and "Search by Image" features for allowing the users to search words by speaking and by giving images. In May 2012, Google introduced a new Knowledge Graph semantic search feature to customers in the U.S.
The frequency of use of many search terms has reached such a volume that they may indicate broader economic, social and health trends. Data about the frequency of use of search terms on Google (available through Google Adwords, Google Trends, and Google Insights for Search) have been shown to correlate with flu outbreaks and unemployment levels and provide the information faster than traditional reporting methods and government surveys.