How Google Works | How Google Search Engine Works:
How Google works is When you do a Google search, you aren’t actually searching the web, you’re searching Google’s index of the web.
Google does this with software Programmers called spiders.
Spiders start by fetching a few web pages, then they follow the links on those pages and fetch the pages that they point to, and follow all the links on those pages, and fetch the pages they link to and so on, until they’ve indexed a pretty big chunk of the web – many billions of pages stored across thousands of machines.
Now, there are hundreds of thousands of possible results. How does Google decide which few documents I really want?
By asking questions – more than 200 of them. Like, how many times does this page contain your keywords?
Do the words appear in the title, in the URL, directly adjacent? Does the page include synonyms for those words? Is this page from a quality website or is it low quality, even spamming?
What is this page’s PageRank?
That’s a formula invented by founders of Google, Larry Page and Sergey Brin, that rates a web page’s importance by looking at how many outside links point to it and how important those links are.
Finally, Google combine all those factors to produce each page’s overall score and send you back your search results about half a second after you submit your search.
Each entry includes a title, a URL and a snippet of text to help me decide whether this page is what I’m looking for. I also see links to similar pages, Google’s most recent stored version of that page and related searches that I might want to try next. And sometimes, along the right and at the top, I’ll see ads and deliver the best possible audience for advertisers and to strive to show only ads that you really want to see.
Google is very careful to distinguish your ads from regular search results, and it won’t show you any ads at all if it can’t find any that Google think will help you find the information you’re looking for – I hope that this made Google a little bit more understandable.
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