---
title: "Hydration: glossary: Agent Ready HTML"
description: "Hydration defined: The step where client JavaScript attaches event handlers to server-rendered HTML. The content is already present before it happens."
canonical: https://agentreadyhtml.com/glossary/hydration/
site: "Agent Ready HTML"
last_updated: 2026-11-04
section: "Glossary"
---

# Hydration: glossary: Agent Ready HTML

> Hydration defined: The step where client JavaScript attaches event handlers to server-rendered HTML. The content is already present before it happens.

Source: https://agentreadyhtml.com/glossary/hydration/
Site: Agent Ready HTML
Last reviewed: 2026-11-04

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

## Where it shows up on this site

-   [Initial HTML reference](https://agentreadyhtml.com/initial-html/)

## Neighbouring terms

-   [App shell](https://agentreadyhtml.com/glossary/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](https://agentreadyhtml.com/glossary/initial-html/): The HTML document a server returns for a URL before any JavaScript runs.
-   [Rendered HTML](https://agentreadyhtml.com/glossary/rendered-html/): The DOM after a browser has run the page scripts.
-   [HTTP Link header](https://agentreadyhtml.com/glossary/http-link-header/): A response header carrying link relations (RFC 8288), so a CDN can advertise files without changing markup.

## Sources

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

Last reviewed 4 November 2026

Edition

Crawl

2026-11-04

Page updated

2026-11-04

Method

How the viewer reads a page, how a file is graded and how a platform is scored: [the method page](https://agentreadyhtml.com/method/).