So how does Google work?
When you type a search phrase into Google, it checks the pattern of various website signals, or ranking factors, such as how relevant your site is, to return a list of sites that match your search.
Most people don’t realize that Google isn’t doing a live search of the entire internet every time someone types something into the search bar. It’s actually searching a stored copy of all of the sites that Google has discovered. This copy is called the Google Index.
To form the index, Google uses small programs called “spiders” to crawl the web. Each spider works the same way: It starts on a single page, then follows the links on that page, looking at content on the next pages, and so on.
As web content gets crawled, it’s stored in Google’s servers, and the index is built. The spiders work at a mind-blowing scale, constantly crawling trillions of pages at an incredibly fast pace. This ensures that the index is as up-to-date as possible and new sites and connections are discovered quickly.