The HTML Standard is a kitchen sink full of technologies for the web. It includes the core markup language for the web, HTML, as well as numerous APIs like Web Sockets, Web Workers, localStorage, etc.
This document explains the syntax, vocabulary and the available APIs for HTML5 documents, focussing on simplicity and practical applications for beginners while also providing in depth information for more advanced web developers.
W3C Semantic Web group's webapp implementation of pyRDFa: parse RDFa from a URL, uploaded file, or text area; get bookmarklets to parse RDFa directly from the current page.
My experience with document interchange led me to classify document formats using the essential distinction that some are "programmable" and some are not. [..]
The reason that this distinction is essential with respect to document interchange is that extracting information from documents in "programmable" document formats is equivalent to the halting problem. That is, it is arbitrarily difficult and cannot be automated in a general fashion.
For example, I conjecture that it is impossible to write a program that will extract the third word from a TeX document.