Obsolete vs. Deprecated HTML

Question

What is the difference between the terms \"obsolete\" and \"deprecated\" with regards to HTML? I seem to be seeing a lot of elements being flagged as \"obsolete\" in HTML5..

Answer 1

In your question, you reference a blog post that subsequently links to the W3 specification regarding obsolete elements.

http://www.w3.org/TR/html5/obsolete.html#obsolete

So as the blog you linked to eludes, obsolete elements should never be used, there are alternatives available. For deprecated elements, browsers will generally still support and render them for backwards-compatibility, but your page will not pass conformance validation.