Search engines, such as Google, which help us find useful information on the World Wide Web, are taken by granted by most of us. There are an astounding 150 million+ websites on the internet currently, according to Netcraft. So, how exactly does Google sift through this astounding number of websites, and find information relevant to your query?
The answer is that Google uses algorithms, which are complex mathematical instructions that tell computers how to carry out assigned tasks. When you type in a query, Google’s algorithm essentially searches out webpages that contain the keywords of your query. It then assigns a rank to each page, based on a number of factors ( e.g. how many times the keyword appears on the page).
The higher ranked pages are usually at the top of Google’s search engine results page (SERP). Therefore, you usually get the best links relating to your search query at the top of the list.
As Google is now not only the world’s most visited search engine site, but the most visited website itself (and also the worlds first $100 billion brand), being listed prominently on Google can result in a big boost in traffic for a website.
Google’s keyword search function is similar to other search engines- automated programs called spiders travel across the web, link to link, building up an index page, which contains certain keywords. This index is what is referred to, when a user enters a search query. Google lists the pages that contain the same keywords that are in your search terms.
A big part in how Google finds sites is played by Keyword placement. When Google looks for keywords in a webpage, any keyword in the webpages title or heading is given extra importance. Headings to come in ranges of different size, and the keywords in the larger headings are more valuable than if they were in smaller headings.
Google’s patented PageRank system
Arguably, the most important feature of the Google algorithm is the PageRank system. It is an automated process that determines where each search result appears on Google’s search engine results page. As most people only look at the first few search results, having a webpage at the top will be likely to generate a lot of traffic for a website.
And how are these results standings determined? Well, we don’t exactly know- the official algorithm is kept secret by Google. What we know do know is:
- Every search result is assigned a score by PageRank. The higher the score, the further up the search results will appear.
- Because pages with good quality content usually have lots of trackbacks (i.e. other webpages link to the target page), the scores are partially determined by the number of trackbacks a target page has.
- Trackbacks from higher webpages count more than the lower ranking sites.
- Other factors which affect the score are the longevity of the site, the strength of the domain name, the age of link going to and from the site. Sites that have been around for a while usually have more value placed onto them by Google.
This sort of strategy works quite well as, by focusing on links going to and from a webpage, the search engine can organise results in a very useful way. Arguably, the best way for your website to get a top spot, is to consistently churn out high quality content, as this will result in more webpages linking to you.
[...] we see in the results of those searches, via their secret algorithm(s). The best we can do is guess at what’s involved in the rankings, which still doesn’t leave us in any more control of the [...]