February 1st, 2012
Search engines are designed to do one thing — make sense of the various documents found on the Web. Originally using just on-page factors like content and meta information contained in specialized tags, search engines moved to analysis of links in the late 90′s with the advent of the PageRank algorithm. This new method treated links as “votes” for websites, using anchor text and website clout to determine what is relevant to a search query. Recently, though still relying on links as the main source for determining a page’s worth, search engines and other Internet spiders are returning to on-page factors to find information that’s meaningful to users.

“New” On-Page Meta
These “new” on-page factors are the culmination of work dating back to the beginning of the modern Internet. The original diagram showing the basics of how the Web would work devotes much of its space to showing the connections between pages, but one corner lays the foundation for what is now known as the semantic web. This image shows a few of the basic properties in the semantic web: rel=author and other relationship markups, Schema’s breadcrumbs and on-page descriptions, and the hCard microformat.
...