Unlike say C++, the core concepts of HTML5 are simple. The difficulty for beginners is not HTML's complexity but that it usually comes cloaked in an all but impenetrable fog of jargon, acronyms and just plain bad writing. Most think of computers as logical – and indeed they are perfectly logical to other computers. The problem is that computer logic is different from human logic. Unfortunately many of those that do understand computer logic are also different. 

That difference is no small part of what makes them good at computers – but bad at explaining computers to the rest of us. They just don't get what we don't get. Duncan Aitken in this tutorial proceeds by saying that HTML5 might look like rocket science, but it's not. His goal is to give you a good solid start on doing just that.