The life span of a Google query is less then 1/2 second, and involves quite a few steps before you see the most relevant results. Here’s how it all works.
Crawling: Google searches the web with automated programs called crawlers, looking for pages that are new or updated. Google stores those page addresses (or page URLs) in a big list to look at later. … Google analyzes the content, images, and video files in the page, trying to understand what the page is about.