Google’s New Sitelinks
Google Products Sep 19, 2006

Google’s New Sitelinks
Google recently started to include a set of links below some results to pages within the site. These new additional links are called Sitelinks. It seems that Google displays Sitelinks if a website is an authority site for the search term.
What are Google Sitelinks?
Google explains the new links on its webmaster pages:
How do you compile the list of links shown below some search results? The links shown below some sites in our search results, called Sitelinks, are meant to help users navigate your site. Our systems analyze the link structure of your site to identify shortcuts that save users time and help them quickly find the information they need.
We only show Sitelinks for results when we think they’ll be helpful to the user. If the structure of your site doesn’t allow our algorithms to find suitable Sitelinks, or we don’t believe the Sitelinks for your site are relevant to the user’s query, we won’t show them.
Currently, Sitelinks are entirely automated. We’re always working to improve our Sitelinks algorithms, and we may incorporate webmaster input in the future.
How does Google calculate Sitelinks?
Google claims that the Sitelinks are created automatically. If Google uses an algorithm to calculate Sitelinks, there must be a way to influence that algorithm.
There are several theories on how Sitelinks are calculated:
1. Google might track the number of clicks for different results. If a website receives a lot of traffic for a specific keyword, it will likely appear with Sitelinks on Google’s search results page. For example, if you use a special trademark term on your web pages that cannot be found on other websites, then many people will click on your website in Google’s results when they search for that term.
Your website will likely appear in Sitelinks for this search term.
2. The link architecture of a website can be helpful. Links at the top of a website’s HTML source seem to have a better chance of being included as Sitelinks.
3. Google might use the Google toolbar to determine Sitelinks. The more often a page is bookmarked, the more likely it is to be used as a Sitelink. Google’s toolbar can collect a lot of information about a website.
Currently, it’s hard to determine how Google calculates the new Sitelinks.
It’s probably a combination of click data, toolbar data, and other factors. If you see Sitelinks for your website, then Google has probably classified your website as an authority site for the search term.