Rich Snippets, Semantic web, Linked Data and SEO
You probably all have noticed that Google is displaying more and more rich snippets in its SERPs. These snippets include various information such as number of reviews, rating, price range, author, format, etc.
These rich snippets are made possible thanks to two major open standards called Microformats and RDFa that are now supported by the major search engines. In that matter, Yahoo has been leading the way since 2006, and we had to wait until May 2009 for Google to start supporting them. As far as I know, Bing hasn’t made any official annoucement about supporting microformats yet, but seems to be supporting them somehow (see below).
Bing result for my favourite cafe in NY:
The microformats and RDFa are two elements of a broader project of semantic web called Linked Data initiated by Tim Berners-Lee. The basic principles is to mark-up the html using specific tags to make the information richer on the page.
The rich snippets are a direct consequence of this initiative, making these SERPs results more interesting for the users as well as for the webmasters who are encouraged to use them to gain more real-estate on the SERPs.
Three major types of information can be marked-up with Microformats: Reviews (hReview), Product information (hProduct )or Contact details (hCard). The same can be done using RDFa.
If you go and have a look at the citysearch page above, or at any Linkedin profile page, you will notice that the microformats or RDFa are being used in different orders, often mixed together. This is just to say this standards are flexible, and Google is getting very good at picking them up.
So what are the uses for SEO? Well for instance, you might want to mark-up the “Contact-Us” page to help the search engines pick up the contact details and improve local business rankings. When optimising websites selling or promoting products and/or services, you can use microformats to markup the product title, description, brand, price, review etc, or use them to markup reviews like most shopping websites already do.
Besides, some other standard are emerging such as the video microformats, and its RDFa equivalent based on the Dublin Core Meta Data Initiative. You won’t be surprised if such initiatives start spreading for images, and think about the potential of marking up social media profiles.Anyways, before publishing your page, you can use the rich snippet testing tool from Google. For instance, the test of the result above gives a similar result below, but when I tested my Linkedin public profile, the test displayed my location and position, but these are not appearing in Google.
One thing to bear in mind when it comes to rich snippets, there are no clear guidelines from the search engines, and they always mention that they “may” use them for their SERPs.
This evolution of the web to the semantic web will enable users to search through more and richer data, potentially being marked up by dozens of different tags referencing each others, inter-linking the web and therefore providing a new dimension called Linked Data.
The search engines are well aware of this, and the more they use these new dimensions, the more relevant their results will be.