Editing Google Search (section)

== Search indexing ==
{{See also|Googlebot}}Google [[Search engine indexing|indexes]] hundreds of [[terabyte]]s of information from [[web page]]s.<ref name="Seeker indexing">{{Cite web |last=Dominguez |first=Trace |date=September 2, 2015 |title=How Much of the Internet Is Hidden? |url=https://www.seeker.com/how-much-of-the-internet-is-hidden-1792697912.html |access-date=December 9, 2017 |website=[[Seeker (media company)|Seeker]] |publisher=[[Group Nine Media]] |archive-date=December 10, 2017 |archive-url=https://web.archive.org/web/20171210015629/https://www.seeker.com/how-much-of-the-internet-is-hidden-1792697912.html |url-status=live }}</ref> For [[website]]s that are currently down or otherwise not available, Google provides links to [[Cache (computing)|cached]] versions of the site, formed by the search engine's latest indexing of that page.<ref>{{Cite web |title=View web pages cached in Google Search Results |url=https://support.google.com/websearch/answer/1687222 |access-date=December 9, 2017 |website=Google Search Help |archive-date=December 18, 2017 |archive-url=https://web.archive.org/web/20171218164019/https://support.google.com/websearch/answer/1687222 |url-status=live }}</ref> Additionally, Google indexes some file types, being able to show users [[Portable Document Format|PDFs]], [[Word document]]s, [[Excel spreadsheet]]s, [[Microsoft PowerPoint|PowerPoint presentations]], certain [[Adobe Flash|Flash multimedia content]], and [[plain text]] files.<ref>{{Cite web |last=Boswell |first=Wendy |date=November 1, 2017 |title=How to Use Google to Find and Open Files Online |url=https://www.lifewire.com/use-google-to-find-open-files-3482196 |access-date=December 9, 2017 |website=[[Lifewire]] |publisher=[[Dotdash]] |archive-date=December 10, 2017 |archive-url=https://web.archive.org/web/20171210015614/https://www.lifewire.com/use-google-to-find-open-files-3482196 |url-status=live }}</ref> Users can also activate "[[SafeSearch]]", a filtering technology aimed at preventing explicit and pornographic content from appearing in search results.<ref>{{Cite web |title=Block explicit results on Google using SafeSearch |url=https://support.google.com/websearch/answer/510 |access-date=December 9, 2017 |website=Google Search Help |archive-date=April 6, 2018 |archive-url=https://web.archive.org/web/20180406005408/https://support.google.com/websearch/answer/510 |url-status=live }}</ref>

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.<ref name="Seeker indexing" /><ref>{{Cite web |last=Rosen |first=JJ |date=May 3, 2014 |title=The Internet you can't Google |url=http://www.tennessean.com/story/money/tech/2014/05/02/jj-rosen-popular-search-engines-skim-surface/8636081/ |access-date=December 9, 2017 |website=[[The Tennessean]] |publisher=[[Gannett Company]]}}</ref><ref>{{Cite journal |last1=Sherman |first1=Chris |last2=Price |first2=Gary |date=May 22, 2008 |title=The Invisible Web: Uncovering Sources Search Engines Can't See |publisher=[[University of Illinois at Urbana–Champaign]] |website=Illinois Digital Environment for Access to Learning and Scholarship |hdl=2142/8528}}</ref>

In 2012, Google changed its search indexing tools to demote sites that had been accused of [[Online piracy|piracy]].<ref>{{Cite magazine |last=Albanesius |first=Chloe |date=August 10, 2012 |title=Google to Demote Sites With 'High Number' of Copyright Complaints |url=http://uk.pcmag.com/search-products/61328/news/google-to-demote-sites-with-high-number-of-copyright-complai |access-date=December 9, 2017 |magazine=[[PC Magazine]] |publisher=[[Ziff Davis]]}}</ref> In October 2016, Gary Illyes, a webmaster trends analyst with Google, announced that the search engine would be making a separate, primary web index dedicated for mobile devices, with a secondary, less up-to-date index for desktop use. The change was a response to the continued growth in mobile usage, and a push for web developers to adopt a mobile-friendly version of their websites.<ref>{{Cite news |last=Schwartz |first=Barry |date=October 13, 2016 |title=Within months, Google to divide its index, giving mobile users better & fresher content |work=Search Engine Land |url=https://searchengineland.com/google-divide-index-giving-mobile-users-better-fresher-content-261037 |access-date=December 9, 2017 |archive-date=December 9, 2017 |archive-url=https://web.archive.org/web/20171209204052/https://searchengineland.com/google-divide-index-giving-mobile-users-better-fresher-content-261037 |url-status=live }}</ref><ref>{{Cite web |last=Roberts |first=Hannah |date=October 27, 2016 |title=Google is splitting its search index to target 'stripped down' mobile websites |url=http://nordic.businessinsider.com/google-changing-index-splitting-into-desktop-and-mobile-2016-10 |access-date=December 9, 2017 |website=[[Business Insider]] |publisher=[[Axel Springer SE]] |archive-date=December 9, 2017 |archive-url=https://web.archive.org/web/20171209204115/http://nordic.businessinsider.com/google-changing-index-splitting-into-desktop-and-mobile-2016-10 |url-status=live }}</ref> In December 2017, Google began rolling out the change, having already done so for multiple websites.<ref>{{Cite web |last=Perez |first=Sarah |date=December 20, 2017 |title=Google's mobile-first search index has rolled out to a handful of sites |url=https://techcrunch.com/2017/12/20/googles-mobile-first-search-index-has-rolled-out-to-a-handful-of-sites/ |access-date=December 21, 2017 |website=[[TechCrunch]] |publisher=[[Oath Inc.]] |archive-date=December 20, 2017 |archive-url=https://web.archive.org/web/20171220160026/https://techcrunch.com/2017/12/20/googles-mobile-first-search-index-has-rolled-out-to-a-handful-of-sites/ |url-status=live }}</ref>

=== "Caffeine" search architecture upgrade ===
In August 2009, Google invited web developers to test a new search architecture, codenamed "Caffeine", and give their feedback. The new architecture provided no visual differences in the user interface, but added significant speed improvements and a new "under-the-hood" indexing infrastructure. The move was interpreted in some quarters as a response to [[Microsoft]]'s recent release of an upgraded version of its own search service, renamed [[Bing (search engine)|Bing]], as well as the launch of [[Wolfram Alpha]], a new search engine based on "computational knowledge".<ref>{{Cite news |last=Barnett |first=Emma |date=August 11, 2009 |title=Google reveals caffeine: a new faster search engine |work=[[The Daily Telegraph]] |url=https://www.telegraph.co.uk/technology/google/6009176/Google-reveals-caffeine-a-new-faster-search-engine.html |url-status=live |url-access=subscription |access-date=December 9, 2017 |archive-url=https://ghostarchive.org/archive/20220110/https://www.telegraph.co.uk/technology/google/6009176/Google-reveals-caffeine-a-new-faster-search-engine.html |archive-date=January 10, 2022}}{{cbignore}}</ref><ref>{{Cite web |last=Fox |first=Vanessa |date=August 10, 2009 |title=Google Caffeine: Google's New Search Engine Index |url=https://searchengineland.com/caffeine-googles-new-search-index-23823 |access-date=December 9, 2017 |website=[[Search Engine Land]] |archive-date=December 10, 2017 |archive-url=https://web.archive.org/web/20171210071617/https://searchengineland.com/caffeine-googles-new-search-index-23823 |url-status=live }}</ref> Google announced completion of "Caffeine" on June 8, 2010, claiming 50% fresher results due to continuous updating of its index.<ref>{{Cite web |last=Fox |first=Vanessa |date=June 8, 2010 |title=Google's New Indexing Infrastructure "Caffeine" Now Live |url=https://searchengineland.com/googles-new-indexing-infrastructure-caffeine-now-live-43891 |access-date=December 9, 2017 |website=[[Search Engine Land]] |archive-date=December 10, 2017 |archive-url=https://web.archive.org/web/20171210071639/https://searchengineland.com/googles-new-indexing-infrastructure-caffeine-now-live-43891 |url-status=live }}</ref>

With "Caffeine", Google moved its back-end indexing system away from [[MapReduce]] and onto [[Bigtable]], the company's distributed database platform.<ref>{{Cite web |last=Metz |first=Cade |date=September 9, 2010 |title=Google search index splits with MapReduce |url=https://www.theregister.co.uk/2010/09/09/google_caffeine_explained |access-date=December 9, 2017 |website=[[The Register]] |publisher=Situation Publishing |archive-date=December 10, 2017 |archive-url=https://web.archive.org/web/20171210020001/https://www.theregister.co.uk/2010/09/09/google_caffeine_explained |url-status=live }}</ref><ref>{{Cite web |last=Metz |first=Cade |date=August 14, 2009 |title=Google Caffeine: What it really is |url=https://www.theregister.co.uk/2009/08/14/google_caffeine_truth/ |access-date=December 9, 2017 |website=[[The Register]] |publisher=Situation Publishing |archive-date=December 23, 2017 |archive-url=https://web.archive.org/web/20171223224328/http://www.theregister.co.uk/2009/08/14/google_caffeine_truth |url-status=live }}</ref>

=== "Medic" search algorithm update ===
In August 2018, [[Danny Sullivan (technologist)|Danny Sullivan]] from Google announced a broad core algorithm update. As per current analysis done by the industry leaders Search Engine Watch and Search Engine Land, the update was to drop down the medical and health-related websites that were not user friendly and were not providing good user experience. This is why the industry experts named it "Medic".<ref>{{Cite web |last=Schwartz |first=Barry |date=August 9, 2018 |title=Google's Aug. 1 core algorithm update: Who did it impact, and how much |url=https://searchengineland.com/googles-august-first-core-algorithm-update-who-did-it-impact-and-how-much-303538 |website=[[Search Engine Land]] |access-date=August 23, 2018 |archive-date=August 23, 2018 |archive-url=https://web.archive.org/web/20180823174248/https://searchengineland.com/googles-august-first-core-algorithm-update-who-did-it-impact-and-how-much-303538 |url-status=live }}</ref>

Google reserves very high standards for YMYL (Your Money or Your Life) pages. This is because misinformation can affect users financially, physically, or emotionally. Therefore, the update targeted particularly those YMYL pages that have low-quality content and misinformation. This resulted in the algorithm targeting health and medical-related websites more than others. However, many other websites from other industries were also negatively affected.<ref>{{Cite web |title=Google Medic Update: Google's Core Search Update Had Big Impact On Health/Medical Sites |url=https://www.seroundtable.com/google-medic-update-26177.html |access-date=March 11, 2019 |website=seroundtable.com |date=August 8, 2018 |archive-date=March 21, 2019 |archive-url=https://web.archive.org/web/20190321033704/https://www.seroundtable.com/google-medic-update-26177.html |url-status=live }}</ref>