- Fizz: An SSR renderer that converts a React Tree to HTML and streams it, showing ready UI in the browser first
- Flight: A protocol that serializes and streams a React Server Component Tree as an RSC Payload so client-side React can understand the tree and the references it needs
- Flight uses its own serialization rules to deliver data in a form React can understand. In particular, it represents a Client Component as a module reference rather than the code itself, allowing it to connect to the code in the client bundle.