[cf100clunk]

I found an introduction link up at the right of the upper-left logo, under Documentation:

https://threlte.xyz/docs/learn/getting-started/introduction

  Threlte is a renderer and component library for using Three.js in a declarative and
  state-driven way in Svelte apps. It provides strictly typed components for deep
  reactivity and interactivity out-of-the-box.