Search information by crawling The web is a continuous growing library with billions of books and no central filing system. Search engine especially Google use software called as web crawlers to identify publicly available webpages. Crawlers analyse the webpages and follow links on those pages, much like you would if you were browsing content on the web. Crawlers go from link to link and bring data about those webpages back to Google’s servers. Search algorithms Google ranking systems sort through hundreds of billions of webpages in the Search index to give you useful and relevant results in a fraction of a second. Useful responses With more content and in a wider variety on the Internet than ever before, Google makes sure to offer you search results in a range of rich formats to help you find the information you’re looking for quickly. To read more How Search Works : https://www.google.com/search/howsearchworks/