I’ve been looking recently into making more use of structured HTML, or microdata. Using these structures means that the meaning of information contained within websites can be more easily understood by search engines. In turn this means the search engines can display more useful and relevant data to their users.
Where it’s easy for you or I to look at a web page and know it’s about music or news or photography, search engines have to try and figure this out from the text contained within the site. So microdata is an attempt to let search engines make sense of what they are indexing on the web.
Click the image to the right to see the results of a Google search for a page (in this case from Last.fm) that contains microdata. The use of microdata has made it possible for Google to understand that the page contains tracks by Lady Gaga and then format its search results in a more useful way.