Google uses bots to rank websites. The process takes three steps:
Bots crawl site’s pages to find new ones.
The next step is indexing, when a Google bot analyzes the content on a web page to understand what it’s about. The results are stored in Google index — a huge database with information about all web pages.
The third step includes serving and ranking. When a user searches for something, Google goes to the Google index to find the most relevant results.