HTML Document Outline
Rules of Thumb
<h1> the main heading of your page, then use
<h6>, etc. in a proper hierarchy without skipping levels.
<section> can be used with aria-label to signal to a screen reader user where a particular sub-part of an article begins and ends. Otherwise, forget about it, or use another element, such as
<aside aria-label=”quick summary”> or
<div role=”region” aria-label=”quick summary”>.
<nav> are very useful for screen reader users, and entirely transparent to those who don’t use assistive technology. So use them.
<article> isn’t just for blog posts — it’s for any self-contained thing. It also helps WatchOS display your content properly.