AMP-HTML

AMP-HTML is an HTML5-based markup language that's used to write AMP content. It's basically a flavor of HTML5 designed with performance in mind. It both restricts and extends the HTML tags you can use in your pages. It restricts the HTML tags you can use to ensure reliable performance, and it provides a set of custom HTML tags--AMP components--to deliver rich but constrained functionality on top of the permitted HTML tags.

Because they are HTML-based, AMP pages will run in any web browser, out of the box. Additionally, AMP-HTML is designed so that it can also be served from the AMP Cache, and when it is, further optimizations can be automatically applied.