Server Components are a new type of React component that run exclusively on the server, not in the browser. Introduced officially with React 18 and expanded with React 19, Server Components allow developers to offload heavy logic, data fetching, and rendering to the server. Instead of shipping large bundles of JavaScript to the client, React can now send lightweight rendered content over the network.

Unlike traditional React components (which run in the browser), Server Components never end up in the final JavaScript bundle sent to users. They are rendered on the server and streamed to the client, improving performance and reducing load times.

In short, Server Components are:

• Rendered only on the server
• Never shipped as JavaScript to the client
• Able to fetch data without blocking the client experience
• Designed to improve performance for complex or data-heavy apps

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