An ahead-of-its-time idea about the distributed web and the idea of open data. See <a href="http://xmlns.com/foaf/spec/" rel="nofollow">http://xmlns.com/foaf/spec/</a> and <a href="https://en.wikipedia.org/wiki/Semantic_Web" rel="nofollow">https://en.wikipedia.org/wiki/Semantic_Web</a> for more high-level details