System Design · Middle · Question 63 of 75

When should heavy computation move to a Web Worker?

✓Correct answer: When it would block the main thread long enough to freeze input or animations (parsing large files, image processing)
2Always, for every function
3Never - workers are slower

Explanation

Workers run in parallel but can't touch the DOM; data is passed via messages (or transferable objects).

Further reading

MDN: Web Workers ↗

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