{"id":133070,"date":"2021-04-27T11:11:26","date_gmt":"2021-04-27T16:11:26","guid":{"rendered":"https:\/\/ahrefs.com\/blog\/?page_id=133070"},"modified":"2025-11-13T09:56:56","modified_gmt":"2025-11-13T14:56:56","slug":"how-do-search-engines-work","status":"publish","type":"page","link":"https:\/\/ahrefs.com\/blog\/how-do-search-engines-work\/","title":{"rendered":"How Search Engines Work"},"content":{"rendered":"\n<div class=\"intro-txt\">Search engines work by crawling billions of pages using web crawlers. Also known as spiders or bots, crawlers navigate the web and follow links to find new pages. These pages are then added to an index that search engines\u2014and even AI assistants, like ChatGPT\u2014pull results from.<\/div>\n\n\n\n<p>Understanding how search engines function is crucial if you\u2019re doing SEO. After all, it\u2019s hard to optimize for something unless you know how it&nbsp;works.<\/p>\n\n\n\n<p>That\u2019s what you\u2019ll learn in this&nbsp;guide.<\/p>\n\n\n\n<p>&nbsp;<\/p>\n\n\n\n<div class=\"chapter-list\"><div class=\"h2\">Contents<\/div><div class=\"main-block\" id=\"chapterList\"><\/div><\/div>\n\n\n\n[MAIN_CONTENT]\n\n\n\n<div class=\"chapter-nav-link clearfix\" id=\"section1\"><a class=\"subhead-anchor\" data-tip=\"tooltip__copielink\" rel=\"#section1\"><svg width=\"19\" height=\"19\" viewBox=\"0 0 14 14\" style><g fill=\"none\" fill-rule=\"evenodd\"><path d=\"M0 0h14v14H0z\" \/><path d=\"M7.45 9.887l-1.62 1.621c-.92.92-2.418.92-3.338 0a2.364 2.364 0 0 1 0-3.339l1.62-1.62-1.273-1.272-1.62 1.62a4.161 4.161 0 1 0 5.885 5.884l1.62-1.62L7.45 9.886zM5.527 5.135L7.17 3.492c.92-.92 2.418-.92 3.339 0 .92.92.92 2.418 0 3.339L8.866 8.473l1.272 1.273 1.644-1.643A4.161 4.161 0 1 0 5.897 2.22L4.254 3.863l1.272 1.272zm-.66 3.998a.749.749 0 0 1 0-1.06l2.208-2.206a.749.749 0 1 1 1.06 1.06L5.928 9.133a.75.75 0 0 1-1.061 0z\" style \/><\/g><\/svg><\/a><div class=\"link-text chapter-header\" data-anchor=\"Search engine basics\" data-chapter=\"Search engine basics\" data-image=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/6.svg\" data-num=\"1\" data-section=\"search-engine-basics\"><div class=\"imgHolder\"><img decoding=\"async\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/6.svg\"><\/div><div class=\"content\"><span class=\"ch\">Part 1<\/span><h2>Search engine basics&nbsp;<\/h2><\/div><\/div><\/div>\n\n\n\n<p>Let\u2019s begin by exploring what search engines are, why they exist, and how they make&nbsp;money.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What are search engines?<\/h3>\n\n\n\n<p>Search engines are searchable databases of web content. They\u2019re made up of two main&nbsp;parts:&nbsp;<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Search index.<\/strong> A digital library of information about webpages.&nbsp;<\/li>\n\n\n\n<li><strong>Search algorithm(s)<\/strong>. Computer program(s) tasked with matching results from the search index.<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\">What is the aim of search engines?<\/h3>\n\n\n\n<p>Every search engine aims to provide the best, most relevant results for users. That\u2019s partly how they gain market share.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">How do search engines make&nbsp;money?<\/h3>\n\n\n\n<p>Search engines have two types of search results:&nbsp;<\/p>\n\n\n\n<ol class=\"wp-block-list\">\n<li><strong>Organic results from the search index.<\/strong> You can\u2019t pay to be&nbsp;here.<\/li>\n\n\n\n<li><strong>Paid results from advertisers.<\/strong> You can pay to be&nbsp;here.<\/li>\n<\/ol>\n\n\n\n<p>Each time someone clicks a paid search result, the advertiser pays the search engine. This is known as pay-per-click (PPC) advertising, and it\u2019s why market share matters. More users mean more ad clicks and more revenue.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"1496\" class=\"wp-image-146229\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-search-engines-make-money.png\" alt=\"How search engines make money\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-search-engines-make-money.png 1600w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-search-engines-make-money-455x425.png 455w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-search-engines-make-money-768x718.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-search-engines-make-money-1536x1436.png 1536w\" sizes=\"auto, (max-width: 1600px) 100vw, 1600px\"><\/figure>\n\n\n\n<div><hr class=\"g-devider2\"><\/div><div class=\"chapter-nav-link clearfix\" id=\"section1\"><a class=\"subhead-anchor\" data-tip=\"tooltip__copielink\" rel=\"#section1\"><svg width=\"19\" height=\"19\" viewBox=\"0 0 14 14\" style><g fill=\"none\" fill-rule=\"evenodd\"><path d=\"M0 0h14v14H0z\" \/><path d=\"M7.45 9.887l-1.62 1.621c-.92.92-2.418.92-3.338 0a2.364 2.364 0 0 1 0-3.339l1.62-1.62-1.273-1.272-1.62 1.62a4.161 4.161 0 1 0 5.885 5.884l1.62-1.62L7.45 9.886zM5.527 5.135L7.17 3.492c.92-.92 2.418-.92 3.339 0 .92.92.92 2.418 0 3.339L8.866 8.473l1.272 1.273 1.644-1.643A4.161 4.161 0 1 0 5.897 2.22L4.254 3.863l1.272 1.272zm-.66 3.998a.749.749 0 0 1 0-1.06l2.208-2.206a.749.749 0 1 1 1.06 1.06L5.928 9.133a.75.75 0 0 1-1.061 0z\" style \/><\/g><\/svg><\/a><div class=\"link-text chapter-header\" data-anchor=\"How search engines build their indexes\" data-chapter=\"How search engines build their indexes\" data-image=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/7.svg\" data-num=\"2\" data-section=\"how-search-engines-build-their-index\"><div class=\"imgHolder\"><img decoding=\"async\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/7.svg\"><\/div><div class=\"content\"><span class=\"ch\">Part 2<\/span><h2>How search engines build their indexes&nbsp;<\/h2><\/div><\/div><\/div>\n\n\n\n<p>Each search engine has its own process for building a search index. Below is a simplified version of the process Google uses.<sup><a href=\"#references\">[1]<\/a><\/sup><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1800\" height=\"942\" class=\"wp-image-146230\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-google-builds-its-index.png\" alt=\"How Google builds its search index\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-google-builds-its-index.png 1800w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-google-builds-its-index-680x356.png 680w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-google-builds-its-index-768x402.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/how-google-builds-its-index-1536x804.png 1536w\" sizes=\"auto, (max-width: 1800px) 100vw, 1800px\"><\/figure>\n\n\n\n<p>Let\u2019s break it&nbsp;down.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">URLs<\/h3>\n\n\n\n<p>Everything begins with a known list of URLs. Google discovers these in many ways, but the three most common are:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>From backlinks.<\/strong> Google has an index of hundreds of billions of webpages.<sup><a href=\"#references\">[2]<\/a><\/sup> If someone links to a new page from a known page, Google can find it from&nbsp;there.<\/li>\n\n\n\n<li><strong>From sitemaps. <\/strong>Sitemaps tell Google which pages and files you think are important on your site.<sup><a href=\"#references\">[3]<\/a><\/sup><\/li>\n\n\n\n<li><strong>From URL submissions.<\/strong> Google lets site owners request crawling of individual URLs in <a href=\"https:\/\/search.google.com\/search-console\/about\">Google Search Console<\/a>.<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\">Crawling<\/h3>\n\n\n\n<p>Crawling is where a computer bot called a spider visits and downloads known URLs. Google\u2019s crawler is <a href=\"https:\/\/ahrefs.com\/blog\/googlebot\/\">Googlebot<\/a>.<sup><a href=\"#references\">[4]<\/a><\/sup><\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Processing and rendering<\/h3>\n\n\n\n<p>Processing is where Google works to understand and extract key information from crawled pages. To do this, it has to render the page, which is where it runs the page\u2019s code to understand how it looks for&nbsp;users.&nbsp;<\/p>\n\n\n\n<p>Nobody outside of Google knows every detail about this process. But it doesn\u2019t matter. All we really need to know is that it involves extracting links and storing content for indexing.&nbsp;<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Indexing<\/h3>\n\n\n\n<p>Indexing is where processed information from crawled pages gets added to the search index.<\/p>\n\n\n\n<p>The search index is what you search when you use a search engine. AI assistants like ChatGPT, Claude, and Gemini also use search indexes to find webpages. That\u2019s why getting indexed in major search engines like Google and Bing is so important. Users can\u2019t find you unless you\u2019re in the&nbsp;index.&nbsp;<\/p>\n\n\n\n<div class=\"recommendation\"><div class=\"recommendation-title\">Did you&nbsp;know?<\/div><div class=\"recommendation-content\">\n\n\n\n<p>Google owns 91.43% of the search engine market. It can send you more traffic than other search engines, as it\u2019s the one most people use.<sup><a href=\"https:\/\/ahrefs.com\/seo\/how-do-search-engines-work#references\" data-ahr=\"https:\/\/ahrefs.com\/blog\/how-do-search-engines-work\/#references\">[5]<\/a><\/sup><\/p>\n\n\n\n<\/div><\/div>\n\n\n\n<div><hr class=\"g-devider2\"><\/div><div class=\"chapter-nav-link clearfix\" id=\"section1\"><a class=\"subhead-anchor\" data-tip=\"tooltip__copielink\" rel=\"#section1\"><svg width=\"19\" height=\"19\" viewBox=\"0 0 14 14\" style><g fill=\"none\" fill-rule=\"evenodd\"><path d=\"M0 0h14v14H0z\" \/><path d=\"M7.45 9.887l-1.62 1.621c-.92.92-2.418.92-3.338 0a2.364 2.364 0 0 1 0-3.339l1.62-1.62-1.273-1.272-1.62 1.62a4.161 4.161 0 1 0 5.885 5.884l1.62-1.62L7.45 9.886zM5.527 5.135L7.17 3.492c.92-.92 2.418-.92 3.339 0 .92.92.92 2.418 0 3.339L8.866 8.473l1.272 1.273 1.644-1.643A4.161 4.161 0 1 0 5.897 2.22L4.254 3.863l1.272 1.272zm-.66 3.998a.749.749 0 0 1 0-1.06l2.208-2.206a.749.749 0 1 1 1.06 1.06L5.928 9.133a.75.75 0 0 1-1.061 0z\" style \/><\/g><\/svg><\/a><div class=\"link-text chapter-header\" data-anchor=\"How search engines rank pages\" data-chapter=\"How search engines rank pages\" data-image=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/guide\/ch5.svg\" data-num=\"3\" data-section=\"how-search-engines-rank-pages\"><div class=\"imgHolder\"><img decoding=\"async\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/guide\/ch5.svg\"><\/div><div class=\"content\"><span class=\"ch\">Part 3<\/span><h2> How search engines rank&nbsp;pages&nbsp;<\/h2><\/div><\/div><\/div>\n\n\n\n<p>Discovering, crawling, and indexing content only make up the first part of the puzzle. Search engines also need a way to rank matching results when a user performs a search. This is the job of search algorithms.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">What are search algorithms?<\/h3>\n\n\n\n<p>Search algorithms are formulas that match and rank relevant results from the index. Google uses many factors in its algorithms.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Key Google ranking factors<\/h3>\n\n\n\n<p>Nobody knows every Google ranking factor because Google hasn\u2019t disclosed them. But we do know some key ones. Let\u2019s look at a few of&nbsp;them.<\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Backlinks<\/h4>\n\n\n\n<p>Backlinks are links from a page on one website to another. They\u2019re one of Google\u2019s strongest ranking factors.<sup><a href=\"#references\">[6]<\/a><\/sup> This is probably why we saw a strong correlation between linking domains and organic traffic in our study of over a billion pages.<sup><a href=\"#references\">[7]<\/a><\/sup><\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1800\" height=\"2197\" class=\"wp-image-146231\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic.png\" alt=\"The correlation between referring domains and search traffic\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic.png 1800w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic-348x425.png 348w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic-768x937.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic-1258x1536.png 1258w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/correlation-between-referring-domains-and-search-traffic-1678x2048.png 1678w\" sizes=\"auto, (max-width: 1800px) 100vw, 1800px\"><\/figure>\n\n\n\n<p>It\u2019s not all about quantity, though. Quality matters too. Pages with <a href=\"https:\/\/ahrefs.com\/blog\/high-quality-backlinks\/\">a few high-quality backlinks<\/a> often outrank those with many low-quality backlinks.<\/p>\n\n\n\n<div class=\"recommendation\"><div class=\"recommendation-title\">Did you&nbsp;know?<\/div><div class=\"recommendation-content\">\n\n\n\n<p>You can check backlinks to your website for free in Ahrefs.<\/p>\n\n\n\n<p>Sign up for a free <a href=\"https:\/\/ahrefs.com\/webmaster-tools\">Ahrefs Webmaster Tools<\/a> account, enter your domain in <a href=\"https:\/\/ahrefs.com\/site-explorer\">Site Explorer<\/a><strong>, <\/strong>and go to the <strong>Backlinks<\/strong> report.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1571\" height=\"842\" class=\"wp-image-146241\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/backlinks-ahrefs.png\" alt=\"Backlinks report in Ahrefs' Site Explorer\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/backlinks-ahrefs.png 1571w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/backlinks-ahrefs-680x364.png 680w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/backlinks-ahrefs-768x412.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/backlinks-ahrefs-1536x823.png 1536w\" sizes=\"auto, (max-width: 1571px) 100vw, 1571px\"><\/figure>\n\n\n\n<p>Our crawler is the fifth most active on the web,<sup><a href=\"#references\">[8]<\/a><\/sup> so you\u2019ll see a pretty complete view of your backlinks here.&nbsp;<\/p>\n\n\n\n<\/div><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Relevance<\/h4>\n\n\n\n<p>Relevance is the usefulness of a given result for the searcher. Google has many ways of determining this. At the most basic level, it looks for pages containing the same keywords as the search query. It also looks at interaction data to see if others found the result useful.<sup><a href=\"#references\">[9]<\/a><\/sup><\/p>\n\n\n\n<h4 class=\"wp-block-heading\">Freshness<\/h4>\n\n\n\n<p>Freshness is a query-dependent ranking factor. It\u2019s stronger for searches that call for fresh results.<sup><a href=\"#references\">[9]<\/a><\/sup> That\u2019s why you see a recently published top result for \u201cnew netflix series\u201d but not \u201chow to solve a rubik\u2019s cube.\u201d&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1800\" height=\"1574\" class=\"wp-image-148660\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/11\/freshness-is-a-query-dependant-ranking-factor-1.png\" alt=\"Freshness is a query-dependant Google ranking factor\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/11\/freshness-is-a-query-dependant-ranking-factor-1.png 1800w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/11\/freshness-is-a-query-dependant-ranking-factor-1-486x425.png 486w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/11\/freshness-is-a-query-dependant-ranking-factor-1-768x672.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/11\/freshness-is-a-query-dependant-ranking-factor-1-1536x1343.png 1536w\" sizes=\"auto, (max-width: 1800px) 100vw, 1800px\"><\/figure>\n\n\n\n<h4 class=\"wp-block-heading\">Page speed<\/h4>\n\n\n\n<p><a href=\"https:\/\/ahrefs.com\/blog\/core-web-vitals\/\" data-ahr=\"https:\/\/ahrefs.com\/blog\/advanced-pagespeed-guide\/\">Page speed<\/a> is a ranking factor on desktop and mobile.<sup><a href=\"#references\">[10][11]<\/a><\/sup> But it\u2019s more of a negative ranking factor than a positive one. This is because it negatively affects the slowest pages rather than positively affect lightning-fast pages.<\/p>\n\n\n\n<div class=\"recommendation\"><div class=\"recommendation-title\">Did you&nbsp;know?<\/div><div class=\"recommendation-content\">\n\n\n\n<p>You can check your page speed for free in Ahrefs.<\/p>\n\n\n\n<p>Sign up for a free <a href=\"https:\/\/ahrefs.com\/webmaster-tools\">Ahrefs Webmaster Tools<\/a> account, crawl your website with Ahrefs\u2019 <a href=\"https:\/\/ahrefs.com\/site-audit\">Site Audit<\/a>, then go to the <strong>Performance<\/strong> report. In general, the less red you see, the better.&nbsp;<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1999\" height=\"1219\" class=\"wp-image-146240\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/performance-report-site-audit.png\" alt=\"Performance report in Ahrefs' Site Audit\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/performance-report-site-audit.png 1999w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/performance-report-site-audit-680x415.png 680w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/performance-report-site-audit-768x468.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/performance-report-site-audit-1536x937.png 1536w\" sizes=\"auto, (max-width: 1999px) 100vw, 1999px\"><\/figure>\n\n\n\n<\/div><\/div>\n\n\n\n<h4 class=\"wp-block-heading\">Mobile-friendliness<\/h4>\n\n\n\n<p>Mobile-friendliness has been a ranking factor on mobile and desktop since Google\u2019s switch to <a href=\"https:\/\/ahrefs.com\/blog\/mobile-first-indexing\/\">mobile-first indexing<\/a> in 2019.<sup><a href=\"#references\">[12]<\/a><\/sup><\/p>\n\n\n\n<div><hr class=\"g-devider2\"><\/div><div class=\"chapter-nav-link clearfix\" id=\"section1\"><a class=\"subhead-anchor\" data-tip=\"tooltip__copielink\" rel=\"#section1\"><svg width=\"19\" height=\"19\" viewBox=\"0 0 14 14\" style><g fill=\"none\" fill-rule=\"evenodd\"><path d=\"M0 0h14v14H0z\" \/><path d=\"M7.45 9.887l-1.62 1.621c-.92.92-2.418.92-3.338 0a2.364 2.364 0 0 1 0-3.339l1.62-1.62-1.273-1.272-1.62 1.62a4.161 4.161 0 1 0 5.885 5.884l1.62-1.62L7.45 9.886zM5.527 5.135L7.17 3.492c.92-.92 2.418-.92 3.339 0 .92.92.92 2.418 0 3.339L8.866 8.473l1.272 1.273 1.644-1.643A4.161 4.161 0 1 0 5.897 2.22L4.254 3.863l1.272 1.272zm-.66 3.998a.749.749 0 0 1 0-1.06l2.208-2.206a.749.749 0 1 1 1.06 1.06L5.928 9.133a.75.75 0 0 1-1.061 0z\" style \/><\/g><\/svg><\/a><div class=\"link-text chapter-header\" data-anchor=\"How search engines personalize results\" data-chapter=\"How search engines personalize results\" data-image=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/personalization.svg\" data-num=\"4\" data-section=\"how-search-engines-personalize-search-results\"><div class=\"imgHolder\"><img decoding=\"async\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/svg\/personalization.svg\"><\/div><div class=\"content\"><span class=\"ch\">Part 4<\/span><h2> How search engines personalize results<\/h2><\/div><\/div><\/div>\n\n\n\n<p>Google tailors search results for each user. It uses information such as your location, language, and search history to do this.<sup><a href=\"#references\">[9]<\/a><\/sup> Let\u2019s take a closer look at these things.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Location<\/h3>\n\n\n\n<p>Google uses your location to personalize the results for searches with local intent. That\u2019s why all results for \u201citalian restaurant\u201d are from or about local restaurants. Google knows you\u2019re unlikely to fly halfway around the world for&nbsp;lunch.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\">Language<\/h3>\n\n\n\n<p>Google knows there\u2019s no point in showing English results to Spanish users. That\u2019s why it ranks localized versions of content (if available) to users who speak different languages.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"1800\" height=\"1836\" class=\"wp-image-146233\" src=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/google-ranks-different-results-for-different-languages.png\" alt=\"Google ranks different versions of pages for different languages\" srcset=\"https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/google-ranks-different-results-for-different-languages.png 1800w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/google-ranks-different-results-for-different-languages-417x425.png 417w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/google-ranks-different-results-for-different-languages-768x783.png 768w, https:\/\/ahrefs.com\/blog\/wp-content\/uploads\/2022\/09\/google-ranks-different-results-for-different-languages-1506x1536.png 1506w\" sizes=\"auto, (max-width: 1800px) 100vw, 1800px\"><\/figure>\n\n\n\n<h3 class=\"wp-block-heading\">Search history<\/h3>\n\n\n\n<p>Google saves the things you do and places you go to give you a more personalized <a href=\"https:\/\/ahrefs.com\/blog\/search-experience-optimization\/\">search experience<\/a>.<sup><a href=\"#references\">[13]<\/a><\/sup> You can opt out of this, but most people probably don\u2019t.&nbsp;<\/p>\n\n\n\n<h2 class=\"wp-block-heading\">Key takeaways<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>A search engine consists of two main parts: index and algorithms.<\/li>\n\n\n\n<li>To build its index, it crawls known pages and follows links to find new&nbsp;ones.&nbsp;<\/li>\n\n\n\n<li>The aim of search algorithms is to return the best, most relevant results.<\/li>\n\n\n\n<li>Search result quality is important for building market share.<\/li>\n\n\n\n<li>Nobody knows all of Google\u2019s ranking factors for organic results.<\/li>\n\n\n\n<li>Key ranking factors include backlinks, relevance, and freshness.&nbsp;<\/li>\n\n\n\n<li>Google personalizes its results based on your location, language, and search history.&nbsp;<\/li>\n<\/ul>\n\n\n\n<h2 id=\"references\" class=\"wp-block-heading\">References<\/h2>\n\n\n\n<ol class=\"wp-block-list\">\n<li><a href=\"https:\/\/developers.google.com\/search\/docs\/advanced\/javascript\/javascript-seo-basics\">\u201cUnderstand JavaScript SEO Basics\u201d<\/a>. <em>Google. <\/em>Retrieved August 16th&nbsp;2022.&nbsp;<\/li>\n\n\n\n<li><a href=\"https:\/\/www.google.com\/intl\/en_us\/search\/howsearchworks\/how-search-works\/organizing-information\/\">\u201cOrganizing Information \u2014 How Google Search Works\u201d<\/a>. <em>Google.<\/em> Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/developers.google.com\/search\/docs\/advanced\/sitemaps\/overview\">\u201cLearn about sitemaps\u201d<\/a>.<em> Google.<\/em> Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/developers.google.com\/search\/docs\/advanced\/crawling\/googlebot\">\u201cGooglebot\u201d<\/a>. <em>Google<\/em>. Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/gs.statcounter.com\/search-engine-market-share\">\u201cSearch Engine Market Share Worldwide\u201d<\/a>. <em>Statcounter<\/em>. Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/www.youtube.com\/watch?v=l8VnZCcl9J4&amp;t=1827s\">\u201cGoogle Q&amp;A+ #March\u201d<\/a>. <em>YouTube<\/em>. Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/ahrefs.com\/blog\/search-traffic-study\/\">\u201c90.63% of Content Gets No Traffic From Google. And How to Be in the Other 9.37%\u201d<\/a>. <em>Ahrefs<\/em>. January 31, 2020. Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/radar.cloudflare.com\/verified-bots\">\u201cCloudFlare Radar\u201d<\/a>. <em>CloudFlare<\/em>. Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/www.google.com\/intl\/en_uk\/search\/howsearchworks\/how-search-works\/ranking-results\/\">\u201cRanking Search Results \u2014 How Google Search Works\u201d<\/a>. <em>Google.<\/em> Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/developers.google.com\/search\/blog\/2010\/04\/using-site-speed-in-web-search-ranking\">\u201cUsing site speed in web search ranking\u201d<\/a>. <em>Google. <\/em>Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/developers.google.com\/search\/blog\/2018\/01\/using-page-speed-in-mobile-search\">\u201cUsing page speed in mobile search ranking\u201d<\/a>. <em>Google. <\/em>Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/developers.google.com\/search\/mobile-sites\/mobile-first-indexing\">\u201cMobile-first indexing best practices\u201d<\/a>. <em>Google. <\/em>Retrieved 16th August 2022<\/li>\n\n\n\n<li><a href=\"https:\/\/support.google.com\/websearch\/answer\/54068\">\u201cFind &amp; control your Web &amp; App Activity\u201d<\/a>. <em>Google. <\/em>Retrieved 16th August 2022<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Understanding how search engines function is crucial if you\u2019re doing SEO. After all, it\u2019s hard to optimize for something unless you know how it&nbsp;works. That\u2019s what you\u2019ll learn in this&nbsp;guide. &nbsp; [MAIN_CONTENT] Let\u2019s begin by exploring what search engines are,<span class=\"ellipsis\">\u2026<\/span><\/p>\n<div class=\"read-more\">Read more \u203a<\/div>\n<p><!-- end of .read-more --><\/p>\n","protected":false},"author":114,"featured_media":133071,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-guide.php","meta":{"wp_typography_post_enhancements_disabled":false,"footnotes":""},"categories":[],"coauthors":[336,377,340],"class_list":["post-133070","page","type-page","status-publish","has-post-thumbnail","hentry","odd"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v27.3 - https:\/\/yoast.com\/product\/yoast-seo-wordpress\/ -->\n<title>How Do Search Engines Work? 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