The semantic web has made it to the mainstream in a rather surprising way. Recipe site owners have been marking up plain HTML pages with microformats that allow Google’s spider to understand the meaning of the content. This is much easier than creating two versions of every page – one for humans and one for machines. What I find particularly interesting is the crowd’s use of microformats. It is now possible to foresee a semantic web being built from the ground up with microformats than the top down with XML.
And now for the first time, a mainstream search engine is built entirely around webpages that use microformats and other structured data.
So for instance, Google is able to show a searcher only Pho recipes that use tofu that take less than a half an hour to make, not by searching for pages that include the word “Pho” and “Tofu” and “Recipe”, but by actually knowing that a recipe for something called “Pho” has an ingredient “Tofu” and a listed cooking time of 1 hour (for example, the is done after publisher’s wrapping the word “1 Hour” in a defined HTML tag ()and then interpreting that in the search results ).