How Does Googlebot Work?

Googlebot collects content from websites to build Google's search index. By continuously gathering documents, Googlebot discovers newly created pages and updates on web pages it has previously crawled.

Googlebot uses various algorithms to determine which sites to visit, how frequently to visit them, and how many pages to retrieve.

Googlebot begins processing with a list created from previous sessions. This existing list is then expanded with sitemaps provided by website administrators. Googlebot crawls all elements linked to the websites it visits, detecting new links, new sites, updates made on sites, and dead links. All this collected information is used to update the web index of the Google search engine.

Googlebot creates an index within the limitations specified in the robots.txt files created by website administrators. If a webmaster does not want certain pages on the website to appear in Google search results, they can block Googlebot in the robots.txt file located in the top-level directory of the site. To prevent Googlebot from following links on specific pages, a webmaster can add the nofollow meta tag; and to prevent Googlebot from seeing individual links, they can add rel="nofollow" to those links.

Google tries to include as many sites as possible in its index without overloading the site's bandwidth. If a webmaster determines that Googlebot is using too much bandwidth, they can set a crawl rate on the Google Search Console homepage that will remain valid for 90 days.