How Google Search Works ?


Learn how Google discovers, crawls, and serves web pages
How does Google work? Here is a short version and a long version.
Google gets information from many different sources, including: 
  • Web pages,
  • User-submitted content such as Google My Business and Maps user submissions,
  • Book scanning,
  • Public databases on the Internet,
  • and many other sources.
However, this page focuses on web pages.

Google Search Engine Works

The short version

Google follows three basic steps to generate results from web pages:

Crawling

The first step is finding out what pages exist on the web. There isn't a central registry of all web pages, so Google must constantly search for new pages and add them to its list of known pages. This process of discovery is called crawling.
Some pages are known because Google has already crawled them before. Other pages are discovered when Google follows a link from a known page to a new page. Still other pages are discovered when a website owner submits a list of pages (a sitemap) for Google to crawl. If you're using a managed web host, such as Wix or Blogger, they might tell Google to crawl any updated or new pages that you make.
To improve your site crawling:
  • For changes to a single page, you can submit an individual URL to Google.
  • Get your page linked to by another page that Google already knows about. However, be warned that links in advertisements, links that you pay for in other sites, links in comments, or other links that don't follow the Google Webmaster Guidelines won't be followed.
  • If you ask Google to crawl only one page, make it your home page. Your home page is the most important page on your site, as far as Google is concerned. To encourage a complete site crawl, be sure that your home page (and all pages) contain a good site navigation system that links to all the important sections and pages on your site; this helps users (and Google) find their way around your site.

Google doesn't accept payment to crawl a site more frequently, or rank it higher. If anyone tells you otherwise, they're wrong.

Indexing

After a page is discovered, Google tries to understand what the page is about. This process is called indexing. Google analyzes the content of the page, catalogs images and video files embedded on the page, and otherwise tries to understand the page. This information is stored in the Google index, a huge database stored in many, many (many!) computers.
To improve your page indexing:
  • Create short, meaningful page titles.
  • Use page headings that convey the subject of the page.
  • Use text rather than images to convey content. (Google can understand some image and video, but not as well as it can understand text. At minimum, annotate your video and images with alt text and other attributes as appropriate.)

Serving (and ranking)

When a user types a query, Google tries to find the most relevant answer from its index based on many factors. Google tries to determine the highest quality answers, and factor in other considerations that will provide the best user experience and most appropriate answer, by considering things such as the user's location, language, and device (desktop or phone). For example, searching for "bicycle repair shops" would show different answers to a user in Paris than it would to a user in Hong Kong. Google doesn't accept payment to rank pages higher, and ranking is done pro-grammatically.
To improve your serving and ranking: