Updating google search results
The algorithm computes a recursive score for pages, based on the weighted sum of the Page Ranks of the pages linking to them.
Page Rank is thought to correlate well with human concepts of importance.
Data about the frequency of use of search terms on Google can be openly inquired via Google Trends and have been shown to correlate with flu outbreaks and unemployment levels, and provide the information faster than traditional reporting methods and surveys.
As of mid-2016, Google’s search engine has begun to rely on these deep neural networks.
Previous keyword-based methods of ranking search results, used by many search engines that were once more popular than Google, would rank pages by how often the search terms occurred in the page, or how strongly associated the search terms were within each resulting page.
The Page Rank algorithm instead analyzes human-generated links assuming that web pages linked from many important pages are themselves likely to be important.
Competitors of Google include Baidu and in China; and in South Korea; Yandex in Russia; in the Czech Republic; Yahoo in Japan, Taiwan and the US, as well as Bing and Duck Duck Go.
Despite Google search's immense index, sources generally assume that Google is only indexing less than 5% of the total Internet, with the rest belonging to the Deep web, inaccessible through its search tools.Marissa Mayer, then-vice president of search products and user experience, described the goal of Universal search as "we're attempting to break down the walls that traditionally separated our various search properties and integrate the vast amounts of information available into one simple set of search results.