Conformance, validation, error handling and the philosophy of the living standard.
Applying a reset or normalize strips default styling and, in doing so, exposes the invalid markup you've been hiding.
HTML5's radical commitment to never breaking the billions of pages already out there, and how it pulled it off.
Markup and HTTP are separate layers; knowing where one ends and the other begins saves real debugging pain.
Separating content from presentation, and what <b> and <i> actually mean in a post-CSS, semantic HTML5 world.
"Standards-compliant" means one thing for authors and another for browsers; conflating them starts pointless fights.
Pave the cowpaths, honor the priority of constituencies, choose pragmatism over purity — the values behind the spec.
The WHATWG revolt, the XHTML dead end, and how HTML became a living standard — the plain-English version.
How HTML5 pared down meta http-equiv, gave us the charset shorthand, and which values still earn their keep.
HTML5's quietest revolution wasn't a new tag — it was finally specifying what browsers do when things go wrong.
Well-formed means the syntax parses; valid means the vocabulary is right — and the gap between them bites.
Every few years someone declares the standards process broken; here's why the doom is usually overstated.
The unglamorous but genuine business case for standards: cheaper maintenance, wider reach, and future you.