LESSON 04 / 9·2 min readIntermediate

What are streaming and Suspense?

Try code in the playground
01 Understand02 Recall03 Prepare

Understand the concept

Streaming sends ready parts of a response while slower parts are still being prepared. Suspense defines a boundary that can show fallback UI while compatible child work is pending. Together they let users see useful content sooner instead of waiting for the slowest section to finish.

Important ideas

  • Streaming sends ready parts of the page before every part finishes.

  • Suspense shows a fallback for a subtree that suspends through supported features.

  • A fetch inside an ordinary effect does not automatically activate Suspense.

  • Choose boundaries around meaningful page sections so the loading experience remains understandable.

PAUSE & RECALL

Can you explain it without the notes?

What are streaming and Suspense?

Use your own words. Explain an example and one limitation before checking the explanation.

Check your explanation

Streaming sends ready parts of a response while slower parts are still being prepared. Suspense defines a boundary that can show fallback UI while compatible child work is pending. Together they let users see useful content sooner instead of waiting for the slowest section to finish.

CONNECT IT TO YOUR INTERVIEW

Turn this concept into a clear answer.

  • Suspense does not make every arbitrary async operation or effect automatically suspend rendering.
Practice this concept
YOUR NEXT STEP

Keep connecting the ideas.

Next lesson: Route handler vs Server Action vs middleware/Proxy?

Adapted from 06_REACT_NEXTJS.md · “What are streaming and Suspense?”. Examples are study fragments; framework behavior can depend on your version.