http://www.eversparkinteractive.com – How Does Google Work?
Hi my name is Jason Hennessey, I am one of the founders here at Everspark Interactive, and today I would like to talk about what happens when you do a search on Google.
One of the first things to understand when you do a Google search is that you aren’t actually searching the web; instead what you’re doing is searching Google’s Index of the web. You see Google crawls the web with software programs that they refer to as “Spiders”. These spiders begin by fetching pages on the web, and then what happens is they follow the links that are located on these pages to locate and index new pages, and then they look for links on these new pages and follow those too, and then they look for more links, and more links and more links and more links…resulting in billions of pages getting indexed and stored across thousands of computers located in large data centers all over the world.
Now…suppose I want to buy a toy for my son, I go to Google and type in say “baby toys” and then hit Enter. What happens next is pretty fascinating. The Google algorithm searches their index to find every single page that includes those search terms. In this case there are hundreds of thousands of documents within their index (also known as search results) that contain the words baby and toys. How does Google decide which document I should see?
By looking at over 200 different variables and asking questions…like:
How many times does this page contain your keywords?
Do the words appear in the URL, the Title Tag, the Header Tags, in the body copy of the page?
Does the page contain synonyms for those words?
Is this page from a quality and trusted source or is it a low quality page?
How old is the domain that this page is on? When was it first registered? How long into the future is the domain registered?
How fast did it take for the page to load?
What is the page rank of this page?
That is a patented formula invented by the founders of Google Larry Page and Sergy Brin that rates a web pages importance by looking at how many outside links point to it and how important those links are.
Finally Google then combines all of those factors together to produce each pages overall score and send us back our search results in only a half of second after we submit it. Pretty amazing huh?
Now let’s take a closer look at a search query that really exposes the Google algorithm.
If you were to go to Google and type in the words “Click Here” and press enter you will notice that the Adobe Reader download page ranks pretty high on the first page. One would think what does the Adobe Reader download page have to do with Click Here? Well as I stated earlier, Google is nothing more than a mathematical algorithm that relies on hundreds of signals pertaining to two things relevance and popularity. In this example, the relevance score is extremely low. Nowhere on this page or in the source code does it mention the words “Click Here”. Ok — now let’s peel another layer from the onion and look closer at the popularity of this page.
First using the SEOBook toolbar, I can tell that this page has a page rank of 10. There are only about a dozen or so pages on the web that have a page rank of 10. Even Google itself has a page rank of 9. OK….now let’s look at the amount of backlinks that are pointed back to this page. Using a third party tool, I can tell that this site has almost 14 MILLION backlinks; however what’s more important is the total number of referring domains which looks like 110,000 at the time of filming this video. So what does that mean….14 Million Backlinks from 110,000 Referring Domains? Let’s look at the US Treasury Website; way down here at the footer…you see this link that says Adober Reader? If you click on that it’s going to take you to the Adobe Download page we are studying. By doing a site search on Google, we can see that the treasury.gov site has 436,000 pages indexed on Google, each of these pages all contain a link back to the Adobe Download page. So this would equal 436,000 backlinks from 1 referring domain.
It is more important to increase the amount of relevant referring domains than it is it to increase the overall number of backlinks.