How search works
How search engines workThe five steps from discovery to rankingComponentsThe parts that make a search engine runCrawlingHow bots find and fetch your pagesIndexingHow a page gets stored so it can be foundCheck if indexedFour ways to confirm a page is on GoogleCrawling and indexing
Web crawlersGooglebot, Bingbot and the new AI botsGooglebotHow Google's crawler reads your siteRobots.txtRules, examples and a free testerXML sitemapCreate one, then submit it to GoogleCanonical tagPick the main version of a pageNoindex tagKeep a page out of search resultsRanking and results
Search engine rankingWhy one page appears above anotherGoogle ranking factorsWhat really matters, grouped simplyPageRankHow links pass value between pagesAlgorithmsTF-IDF, PageRank and modern rankingResults page (SERP)What each block on the page is forAI searchHow AI answers are built from the indexUnderstand
What is a search engineA plain definition with real examplesTypes of search enginesCrawler, meta, vertical, private and AIBrowser vs search engineTwo tools that people often mix upExplore
Best search enginesGoogle, Bing, DuckDuckGo and moreUses of search enginesThe everyday jobs that search handlesHistory of search enginesFrom Archie in 1990 to AI answersInteractive tools that let you see how search engines behave instead of only reading about it. They run in your browser, with nothing to install.
All tools
Start with the simulator. It shows the full journey of a page, which makes every other guide on this site easier to follow.
Looking for something to read or print instead? Browse the free search engine resources, including the PDF guide, diagram and glossary.