Hydration is the process of attaching event listeners to the DOM, to make the static HTML interactive.

— Next.js Docs (Rendering: Client Components, Full Page Load)

1. Server sends rendered static page to the browser

2. Browser paints static page (non-interactive view)

3. The JavaScript bundle loads on the client

4. The bundle attaches to the DOM and hydrates it

5. Page becomes interactive with client-side JavaScript

hydration-five.vercel.app/

lucasamonrc/hydration

So...