HTML5 is the overarching standard for everything rendered on the web. This gives it the unique position to sit atop concrete abstractions and decisions like using React or Vue.js. It's the abstraction we're trying to leverage to deliver a framework-agnostic component library and Design System. Specific implementations that are in use in a given project depend on the context, and the size and number of teams implementing (often times different) touch points based on the shared design system and component library.