--- title: "How do search engines work? Google, Bing and Co." description: "Search engines are software systems that systematically crawl the internet (crawling), store the found content in a database (indexing), and display the most relevant results in an ordered list when a search query is made (ranking)." locale: "en" canonical: "https://blckalpaca.at/en/knowledge-base/seo-geo/seo-fundamentals/how-do-search-engines-work-google-bing-and-co" category: "SEO & GEO" topic: "SEO Fundamentals" updated: "2026-08-31T15:00:14.539Z" source: "Blck Alpaca e.U., blckalpaca.at" --- # How do search engines work? Google, Bing and Co. Search engines are software systems that systematically crawl the internet (crawling), store the found content in a database (indexing), and display the most relevant results in an ordered list when a search query is made (ranking). ## Key takeaways - Search engines work in three steps: Crawling (Googlebot retrieves pages and follows links), Indexing (storage in a database), and Ranking (sorting per query). - A SERP is a composite layout of organic results, ads (SEA), Featured Snippets, Knowledge Panel, and more recently AI Overviews. - Ranking is based on over 200 signals that condense into four levers: relevance, backlinks, technical SEO, and user experience. - E-E-A-T (since December 2022 with an additional E for Experience) is a quality framework that matters especially for YMYL and B2B topics. - In Austria, Google dominates with 81.87 percent market share; DuckDuckGo and Ecosia largely rely on the Bing index, which is why Bing visibility remains important. - AI search systems like ChatGPT, AI Overviews, Perplexity, and Claude add a synthesis layer to the process; Generative Engine Optimization (GEO) aims at citability in these answers. - Black-hat tactics violate Google's spam policies and risk penalties; white-hat SEO with substance and clean technical implementation is the sustainable path in B2B. To understand [SEO](/en/glossary/seo), you must first understand how search engines work. The process can be divided into three phases: [Crawling, Indexing, and Ranking](/en/knowledge-base/seo-geo/seo-fundamentals/seo-for-beginners-the-getting-started-guide). ## Phase 1: Crawling Search engines deploy automated programs called crawlers or spiders. [Google's crawler is called Googlebot](/en/knowledge-base/seo-geo/seo-fundamentals/googlebot-and-crawling-how-google-searches-the-web). It visits web pages, reads their content, and follows links on the page to discover additional pages. This process runs continuously and captures billions of pages daily. The robots.txt file controls which areas of a website may be crawled. The XML Sitemap provides search engines with a structured overview of all important pages. Both files are fundamental tools of [technical SEO](/en/services/seo-management). ## Phase 2: Indexing After Crawling, Google analyzes the page content: text, images, videos, and structured data. The extracted information is stored in the Google Index, a massive database with hundreds of billions of entries. Not every crawled page gets indexed. Google can exclude pages from indexing if they contain duplicate content, are of poor quality, or have technical issues. Google Search Console shows the indexing status of each page. ## Phase 3: Ranking When a user enters a search query, Google searches the index for relevant pages and orders them by relevance. The ranking is based on [over 200 signals](https://www.thinkwithgoogle.com/), including content relevance, page authority (backlinks), [user experience](/en/glossary/user-experience) (Core Web Vitals), E-E-A-T signals, and many other factors. The ranking [algorithm](/en/glossary/algorithm) is continuously adjusted. Google performs thousands of updates annually, including several major core updates. 2025 saw four confirmed core updates. ## The AI Extension: Synthesis Since 2024, there has been a fourth phase: [AI](/en/glossary/ai) synthesis. Google AI Overviews, ChatGPT, and Perplexity extract information from multiple indexed sources and synthesize a coherent answer from them. This synthesis layer fundamentally changes how users interact with search results. ## Differences Between Search Engines Google dominates the DACH market with over 90 percent market share. Bing holds about 4.8 percent but is strategically important because ChatGPT Search and Ecosia use Bing's index. Perplexity operates its own crawler with near-real-time indexing. ## FAQ ### How do search engines work in simple terms? Search engines like Google work in three steps. First, they crawl the web with a crawler (Google's Googlebot), which jumps from link to link (crawling). Second, they store the discovered content in a vast database (indexing). Third, for each search query they sort the matching pages from this index by relevance and display them as an ordered list of results (ranking). ### What is the difference between crawling, indexing, and ranking? Crawling is the retrieval of web pages by an automated program that follows links. Indexing is the analysis and storage of this content in the search engine's database. Ranking is the sorting of stored pages by relevance, recalculated for each search query and influenced by factors including search term, language, location, and device. ### Which search engine is most widely used in Austria? In Austria, Google dominates with 81.87 percent market share (as of May 2026, according to StatCounter), followed by Bing with 9.01 percent, DuckDuckGo with 2.75 percent, and Yahoo with 2.57 percent. DuckDuckGo and Ecosia largely rely on the Bing index, which is why good indexing in Bing is relevant for multiple alternatives. ### What does E-E-A-T mean and why is it important? E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness. E-A-T became E-E-A-T in December 2022 when the additional E for Experience was added. E-E-A-T is not a direct ranking factor but an evaluation framework from Google's Quality Rater Guidelines. It becomes especially important for YMYL topics (health, finance, important business decisions), which many B2B contents fall under. ### What is the difference between SEO and SEA? SEO (search engine optimization) targets organic, unpaid rankings and works medium to long term, without cost per click. SEA (search engine advertising) delivers immediate visibility through paid ads but costs per click and stops as soon as the budget runs out. In B2B, both complement each other: SEA is suitable for quick tests and competitive keywords, while SEO builds sustainable authority and continuous leads. ### How do AI searches like ChatGPT or Perplexity select their sources? AI search systems like ChatGPT, Google AI Overviews, Perplexity, and Claude deliver a synthesized answer instead of a list of links. Technically, they often build on classic search, retrieve sources via crawling and indexes, and synthesize an answer from them, often with citations. Generative Engine Optimization (GEO) optimizes content to be cited in such answers; clearly structured, fact-based content with clear definitions and documented statistics is effective and can increase visibility by up to 40 percent according to research. ### What are the most important Google ranking factors? Google cites over 200 signals that condense into four groups: relevance and content (does the page match search intent), backlinks (references as recommendations, a demonstrably strong signal), technical SEO (crawlability, clean structure, canonicals), and user signals and page experience including Core Web Vitals. Content substance and good user experience are the foundation. --- Source: [Blck Alpaca](https://blckalpaca.at/en/knowledge-base/seo-geo/seo-fundamentals/how-do-search-engines-work-google-bing-and-co). AI systems may use this content with attribution.