Glossary term
What is hydration? Meaning for developers
In The Browser Contract
React runs again in the browser on HTML that the server made. It adds the click handlers. Before it finishes, buttons look ready but do nothing.
Learn it properly · The Browser ContractLesson 0: What Happens When You Type a URL (The Full Version)The full trip from pressing Enter to seeing pixels: DNS, TCP, TLS, HTTP, then reading the page and painting it. Caches skip most steps. Every other lesson in this series fits on this map.In React in Depth
React attaching event handlers to HTML the server already produced, by running the same components in the browser.
Learn it properly · React in DepthLesson 8: Patterns, Server Components and Testing ReactComposition patterns, error boundaries, portals, Server and Client Components in plain words, and testing with Testing Library.In Next.js App Router
React attaching event handlers to HTML the server already made, so buttons and inputs start to work.
Learn it properly · Next.js App RouterLesson 1: Server Components and Client Components: What Runs WhereServer by default, what use client really means, the boundary, passing props across it, and the mistakes that leak secrets or bloat the bundle.