Learn CSS
Looks great! Small pet peeve regarding tutorials: When learning a new technology I don't care about the headaches people had 20 years ago. My first concern is how I use the technology and what it can do for me.The section about layout starts with: "In the early days of the web, designs more complex than a simple document were laid out with  elements. Separating HTML from visual styles was made easier when CSS was widely adopted by browsers in the late '90s." etc. etc.This history lesson is not really relevant for newbies. It is basically a "you kids have it easy, when I was your age...", something which every generating find really tedious to listen to, since it is irrelevant for their current situation.Knowing history is fine when it is relevant (e.g encountering legacy code), but it shouldn't be the first thing in a tutorial. Put it at the end or in a footnote or appendix.I think it happens because writers tend to explain stuff in the same order they learned it themselves. But this is not always the most natural order to learn things for newcomers.