The era passed with the recent announcement by Google, Yahoo and Microsoft of the launch of schema.org. Schema.org provides technical documentation on the ways in which the major search engines will recognize structured data in your web pages. It shows how to get rich snippets of content and data from your site directly into search engine results pages. Rich snippets are the next step in the evolution of search, because they allow search engines to read meaningful semantics into content on the web.

If rich snippets sound surprisingly like an application of the semantic web, then it’s for good reason. A huge amount of time and effort has gone into researching how to add layers of machine-readable information to the human-readable web, with the grand view that the machine-readable web would always underpin a new wave of disruptive innovation. Web 3.0 would be the next big thing.

However, Google et al. have chosen not to base the next big thing in search, rich snippets, or semantic web technology. Schema.org eschews RDFa in favor of simpler HTML5 markup.

For years semantic web purists have been preaching that the future is all about RDF and triples. Yet, in the 12 years that theorists have been working on the semantic web, we’ve yet to see many convincing practical uses for the technology. The graph I’ve included above shows the rise and fall of Web 2.0 job postings compared to job posts requiring semantic web technologies. This makes a pretty clear case that the semantic web simply never took off.