Hydration

In short

The step where client JavaScript attaches event handlers to server-rendered HTML. The content is already present before it happens. Example: Next.js describes hydration as attaching event handlers to the DOM to make static HTML interactive. Related terms: App shell, Initial HTML, Rendered HTML, HTTP Link header.

Source of the example

The example in the summary above is from nextjs.org, read 4 November 2026.

Where it shows up on this site

Initial HTML reference

Neighbouring terms

App shell: A near-empty HTML document whose content is injected by JavaScript after load, typically a single div with id root or app.
Initial HTML: The HTML document a server returns for a URL before any JavaScript runs.
Rendered HTML: The DOM after a browser has run the page scripts.
HTTP Link header: A response header carrying link relations (RFC 8288), so a CDN can advertise files without changing markup.

Sources

nextjs.org https://nextjs.org/docs/app/getting-started/server-and-client-components, read 4 November 2026

Last reviewed 4 November 2026