How Does Google Search Engine Work?

While we don’t often think about – or care – how Google works, it is very important for anyone who is using AdSense, AdWords, or natural search marketing for their business to understand the basic principles that drive the Google search engine.

There are three main parts to Google: Googlebot, The Indexer, and the Query Processor. Each of these three parts is crucial to online businesses, believe it or not. Let’s take a look at each of these Google elements to see how they work.

Googlebot is the search engine spider that comes to your website and ‘spider’s’ your pages. It isn’t an actual spider.

It actually works more like a web browser by calling a server and requesting pages, and downloading them – just as you do when you open your web browser, type in an email address, and the page loads.

Googlebot, however, is run by numerous computers and performs this task much faster than one user could on their home or work computer. Googlebot also doesn’t know that a website exists until a URL is put into their Add URL form, or until they find a link to that website on another web page.

When Googlebot visits a page, they take all the links from that page, and put them in a queue for crawling, and just repeat this process over and over again. Once Googlebot has found a link, and downloaded the page, it hands that page off to the Indexer.

The Indexer stores the pages in Google’s Index Database. The Index then sorts all of the pages in its database, alphabetically, by looking at all of the keywords on the pages. The Index does not pay any attention to what Google calls stop words, such as is, on, or, why, how, etc. It just pays attention to more important keyword type words.

The Indexer, after Indexing pages, waits for the Google Query Processor to ask it for a list of documents. A keyword is given to the Query Processor, which in turn asks the Indexer for a list of websites that contain that keyword.

The Indexer then supplies the Query processor with a list of the documents, and the Query processor presents that to the user that requested the keyword.

As you can see, each element is important to the others. It all starts with the Googlebot finding your webpage link on another page, or by you going to Google and using the Add form to list your website.

Hope this helps. More ideas, questions and comments are welcomed.